[nknighthb]

Are you talking about a grandfathered data plan?

On an account just activated in December, I have these options available to me: https://www.dropbox.com/s/0i7witxcmu9qlh1/Screen%20Shot%2020...

None of the ones labelled "unlimited" look like "5GB cap", they look like unlimited on the phone + limited amount of tethered usage. It would seem to make very little sense to offer 5GB + 2.5GB for the same price as a combined total 4.5GB.

[smithzvk]

This is an off-contract pre-paid plan. I believe that you must buy these as SIM kits from Walmart. When I got it, you had to buy it from a physical store, but it looks like you can do it online now though it may take some time for your SIM card to arrive.

Word to the wise, you get basically no T-Mobile customer service once you switch to pre-paid. I have been on contract with them before and they are very helpful, but on pre-paid it seems like you are on your own.

[scurvy]

It's not pre-paid only. You can get it month to month if you buy the SIM starter kit and activate online. You can't get it in T-Mo stores.