wow, I just bought a t-mobile hot spot so I could use my other devices. I am not willing to toss any more doe on chromebooks, but I am curious if the upsale plans in the chromebook are any different than their data offered at the store.
I have plenty of wifi at home and at work, and even on the bus into work (AC Transit in the Bay Area), so chances are I won't be using it all that often. I can tether to my phone as well (Verizon). That said, I can see it coming in handy now and then, and if I were out of town or something I wouldn't hesitate to try one of the on demand plans. Not sure if there is a contract on the monthly plans.
"4G for life. 200MB of free data each month, no annual contract, for the life of your device." according to their site.
I just got one from Costco. It's a bit more than the Samsung ($379 at Costco, a little cheaper at Walmart) but so far I'm liking it.