That unlimited Millenicom 3G/4G plans look to be about the best situation out there for getting both high enough data rates and no caps for streaming of video movies when camping ... assuming their coverage is identical to Verizon's (since they use the Verizon cellular system).
However, I don't think it's convenient or inexpensive to start and stop their plans for use on RV camping trips. Unless you are a full-timer, it's a bit pricey to keep paying $69.99 per month when the RV is sitting in storage just so you can have your hotspot there for camping trips on and off throughout the year.
In our case that $69.99 every month would be in addition to the monthly charge for our home Internet access.
What I would like is a plan like Millenicom's Unlimited Plan that could be turned on and turned off conveniently over the Internet, as needed, for camping trips. Wishful thinking I guess.