Iris or Multiman?

Hi guys, i have always used multiman since i had my first CFW on the ps3 (Kmeaw), but, sometimes, i see a lot of posts saying that multiman is a bloatware and Iris is a better backup manager, so there are my questions:
why is MultiMan a bloatware? What are the main differences between Iris and Multiman? What makes one better than the other? Can Iris download the covers of my games and resign them if they have 4.31 keys? (As Multiman does)

Thanks for the help!