I've been looking at buying an iPad for awhile now and I think T-Mobile has pretty good deal on them. They have the iPad Air LTE for $500. I was wondering if I could go to T-Mobile and just pay in full for the iPad without signing up with them and then use a T-Mobile SIM for 200MB free data. Has anyone tried this? I don't want to do monthly payments and I don't really have any credit right now.