Pre-Paid Data SIM?
 

I'm enquiring about availability of a pre-paid data SIM card for a 2-week visit to the US in Jan 2017. I will be visiting Vail and Park City and driving between them along I-70 with a visit to Moab.

I would presumably be purchasing this SIM somewhere close to DEN airport.

Any suggestions as to the best bet for a data-only pre-paid SIM? I will be using it with a UK-spec 3g/LTE phone, but my understanding is that in the LTE world this is no longer as big a compatibility problem as before.