Prepaid Carrier Question

Hey everyone, I just joined recently and was hoping I could get some suggestions. Sorry for the length of the post.
I am currently with ATT on my parents' family plan. Due to money issues they are switching to MetroPCS for a cheaper plan. I am currently in the Chicago area so I can't use them, or I would. My brother and his wife have nothing but good things to say about them but their home service isn't in Chicago.
In the hopes of finding something comparable and affordable, I have been looking at the prepaid services available here. I've looked at Virgin Mobile, T Mobile, StraightTalk, Cricket, and Boost Mobile. I looked at Net10 as well but they don't have data so that would be a last resort. I'm not a heavy data user but I'd like to be able to play games or facebook and so on.
Costwise, all of the unlimited plans seem to be priced about that same. I was hoping you guys could share some experiences about these carriers to help me make a decision.
If you have (or had) any of these, would you recommend it to a friend? How good is the coverage? Bonus points if you're in the Chi area. Is the customer service really as lousy as I'm reading for all of them? Are there hidden things I should be concerned about? I've never had a phone service by myself so a lot of the lingo is beyond me. For example, Cricket I think said they had unlimited data but then when you looked at the details of the plan, it said the data was $1 per 30mb or something like that. So I'm confused. How does roaming work? How much should one expect in taxes and fees? Can you take your phone number with you? Is it difficult to do? Is it worth it to switch to a prepaid or just deal with one of the big carriers?
If anyone has ANY comments, tips, tricks, suggestions, etc, it would be much, much, much appreciated.
Also, any thoughts on a mid to low range android would be awesome.
Thank you in advance!!!