I did a lot of research on baby gear before my first child was born. I decided to go with the Diaper Genie because it was the first, my friends liked using it, and it seemed to work.
The Diaper Genie has worked well for me and my family. I have friends that prefer other systems that you can use any bag with. I don't mind purchasing the Diaper Genie refills because I think they are the key to minimizing odors. I like that the Diaper Genie helps us keep our changing area clean and fresh. I empty the Genie about twice a week (that is working full-time so many diapers are at daycare). If you care for it properly, you should not notice diaper odors at all.
My only criticisms are the purchasing of bag refills (which I don't mind), little instruction, and it is a bit putzy to figure out. I always forget to instruct people when they come to babysit and NO ONE can figure it out on their own.