I was on T-Mobile's Jump plan with a 32GB iPhone 5s. After experiencing terrible service in my area, I paid off my phone and switched back to AT&T. I get unlimited texts/calling with 2GB of LTE data for $65 a month, no contract. I usually go over my data by no more than 1GB, costing me an extra $15 a month, so figure I pay almost $80 a month for my phone bill. I plan on keeping my 5s for now, since I plan on waiting for the 5.5" model (if the rumors are true). Should I buy the 5.5" outright and sell my 5s after I get it? Or would AT&T's Next plan be a better option for me? I want to keep my monthly bill as low as possible.