The rumor five are the main characters of the story of magia record (I'm unclear on whether sana is supposed to be part of their group or not so I'm just going to ignore her for now). The main problem with every member of the rumor five is that they all start out as 1-2 star girls so their stats even after being raised to 5 stars is not so great.

Iroha tamaki

(5 star awakening art work)
Intro: iroha is the true main character of the game and we follow her as she investigated the disappearance of her sister along with the "uwasa" that are born from monsters
Wish: to cure her sisters disease
Pros:
•easy to raise
•easiest access to additional memoria slots
•her magia has the only revive effect that works after a unit has already died
•good heal and magia gauge fill connect that also comes with an attack up but only at high awakening levels
•she's has fairly good defenses (25 out of 78 5 stars in jp)
•she's free?
Cons:
•lowest attack amongst five stars (78 out of 78 5 stars in jp)
•very low hp (61 out 78 5 stars in jp)
•her connect doesn't become good until she's been awakened into a 4 star
•her magia is more or less useless since it won't do much damage coming from her and she's more likely to die before her teammates, at high rarities it has a heal attached to it but there are much better magia' as that have heals attached to them
•her five star awakening isn't even available in the English server which means she's even weaker and doesn't have access to the heap on her magia or the atk up on her connect
•when the revive effect can be used it's niche and the person revive is likely to die before they can do anything
•the revive is random as far as I can tell
Conclusion: the only reason iroha isn't the worst magical girl in the game is because kuro (the only other 1-star girl) exists, she doesn't have the hp stat to rank or stay alive long enough to do much of anything and even if she does stay alive long enough to get her connect off, chances are there were better disc options during the turns she attacked. The access to more memoria slots for "free" is nice but also kind of fake since you still have to clear the story and her side stories (both of which can get pretty hard). Her unique access to revive is great and in the right teams she might be able to do some work in PvE especially during the early story chapters but in mirrors she's just dead weight.

Yachiyo nanami

(5 star awakening art work)
Intro: yachiyo is iroha'a far more interesting rival turned boss turned friend. It's unclear what has happened in yachiyo's past but she seems to care for magical girls and warns them against coming to kamihana city of they are weak
Wish; to survive
Pros:
•her ABBBC deck helps her to make up for her low attack stat via puella blast chains or even regular blast chains
•her connect has a powerful blast buff on it as well as giving critical hit chance and a heal
•her magia gives blast damage buff and atk up for three turns
•she has fairly good defenses and middling health (25 out of 78 five stars in jp in defense and 48 out of 78 five stars in jp in hp)
•blast discs are possibly the most powerful disc in the game and her entire kit is built around it
•easy access to multiple memoria slots
Cons:
•very low attack stat (69 out of 78 five stars in jp)
•her middling hp stat
•her ABBBC deck means she's not going to be getting off her magia very often if at all
•she has heavy competition from nanaka tokiwa and she loses that competition
•critical hit buffs are inconsistent unless their coming off of Masara kagami's connect
Conclusion: yachiyo is one of the water blast girls that populate mirrors higher levels and make into the hyper offensive game that it is so it's safe to say that she's pretty good. She works well on dedicated blast teams or on teams in which everyone has at least 2 blast cards, she can be treated as a sort of budget Kyoko but with the water element. Her 2 star status gives her very easy access to extra memoria slots which can make all the difference in both PvE and mirrors. Her magia is good but she's probably not going to get it off in mirrors or PvE and in higher level mirrors she might not even be able to get her connect off more than once. Yachiyo can also serve as a decent budget water tank but in mirrors fire element girls, outside of the occasional momoko or Kyoko, don't seem to be that popular. Yachiyo does actually have her 5 star variation avaliable on the English server unlike iroha, Felicia, and Sana. Yachiyo is a good unit for any FTP players out there and defiantly someone you should raise however if you happen to have both her and nanaka tokiwa, is focus on nanaka first.

Tsuruno yui

(5 star awakening art work)
Intro: tsuruno is an energetic and determined girl who used to be in the same magical girl team as yachiyo, her family owns a Chinese restaurant that has had a lot of money problems.
Wish: to win the lottery
Pros:
•a great attack stat considering she's a natural 2 star (38 out of 78 five stars in jp)
•a good connect for blast teams but its still decent for accell teams
•at max awakening her magia comes with blast up, and accell up for the whole team (3 turns) as well as an evade for herself (1 turn)
•easy access to additional memoria slots
•versatile offensive accell-blast unit
Cons:
•lowest health AND defense amongst five stars (78 out of 78 five stars in jp in both stats)
•struggles between wanting a blast team that she can provide support to and receive support from or an accell team that can heal her and let her get off her magia multiple times
•struggle to get off her magia because of her low health and defense
•Struggles to get blast damage in on her own without connect or magia buffs
Conclusion: tsuruno is a hit or miss glass cannon, the difference between her and other glass cannons (such as mami tomoe) is that when everything works out for her she can easily clear any enemy that she has an advantage against but when she gets targeted by one too many attacks, gets bad disc draws for herself or teammates she needs connects from, or she just keeps drawing her 1 charge disc. For PvE content she should do just fine as long as she's being supported by units like aimi eri or yachiyo but in mirrors she's likely to be overpowered and killed by the water blast girls or another water unit before she has a chance to charge her magia or deal much damage with her blast discs.

Felicia Mitsuki

(4 star awakening art work)
Intro: Felicia is an orphan girl who will go wherever the reward is the greatest, she has anger issues when it comes to witches and can be reckless in battle.
Pros:
•good attack stat giving her 2 star base rarity (33 out of 78 five stars in jp)
•her connect provides atk up which can be used to support a team for any of the disc types
•her magia can inflict some major defense downs on her enemy
•at max awakening she can inflict bind on her enemy
•easy access to additional memoria slots
•she's technically never at a disadvantage I guess but the same can be said for iroha
Cons:
•her connect gives counter negate which is almost never useful
•her magia is single target and is likely to kill anything that isn't a boss so the bind chance probably won't matter especially in mirrors
•poor health and defense stats (72 out of 78 5 stars in jp in hp, 73 out of 78 5 stars in defense in jp)
•light type girls are common in mirrors and she takes extra damage form them
•she has 2 charge discs in her deck and charge discs are pretty bad
•5 star awakening isn't available in NA so she doesn't have access to her bind on magia there as well as having lower stats for the time being
Conclusion: Felicia just sort of..... exists. I mean her connect has the same attack up value as tsuruno's but at least tsuruno has a blast damage up also attached to it, she has bind on her magia but so does mami tomoe and mami at least has an aoe magia. Felicia doesn't work in mirrors because she's crumbles in 2 hits and there are almost no units in mirrors that use counter, evade maybe but not counter. If she had one more blast disc then she could be a potential power house in blast teams but she has a charge disc instead which is just bad. Also she only has one accell disc so, just like with yachiyo, she's not very likely to even get her magia off. Felicia could work in boss fights like the amana sisters in which one of the enemies is light type and needs to be dealt with quickly but she's bad in mirrors and there are better single target dark type options for PvE such as Ren Izusu, Kanoko yayoi, and, in some situations, moemura.