Another thing is they only have so many phones that you can actually use on their network.
A bunch of phones are blacklisted so if you go to Samsung or a few other mobile websites and try to get an unlocked phone then its the game of it may or may not work and it sucks because you have to buy phones from their website and it is way more expensive than it is worth.
You also do not have family accounts at visible so everyone has to have their own accounts and lets face it that is a lot of accounts you have to remember and keep up with.
Cricket Wireless uses AT&T network and let me tell you I never had an issue with AT&T. It worked great when I had it way back when.