It is interesting how getting connected in the US as a visitor via cellular has changed over the years from one extreme to the other. While Internet access enabled prepaid SIM cards where available in the past 5 to 6 years in many countries around the world I struggled for many years to get the same thing in the US. At some point AT&T offered mobile data on prepaid SIMs but one had to find an AT&T store and then fiddle with a pretty rough web front-end to activate a data option. Not ideal.
But things have significantly changed recently. When preparing for a business trip to the US I noticed that a number of MVNOs (virtual network operators) have sprung up that offer prepaid SIMs for mobile Internet access specifically for international visitors. Here's a PC Mag article that gives a good overview. I opted for a Ready SIM 500 MB data only SIM for around $20 (including shipping) that remains active for 14 days after first activation. Other options that include voice and and a bigger data bucket are also avaialble. It's a use and throw away SIM as there's not even an option to top-up option. That probably means that have a pretty lean back-end system :-)
The only catch was that I had to find a mobile device that supported Wi-Fi tethering and the US 3G frequency bands of the network used by that MVNO, which were the 1900 MHz and AWS (1700/2100 MHz) bands. That's not so easy anymore as current mobile devices often sacrifice 3G bands for LTE and the AWS band was never very popular for 3G in devices outside North America in the first place. But I managed to get hold of one and I decided to order a 'Ready SIM' to my hotel as there wasn't enough time anymore for international shipping. Next time I'll order it a bit sooner so I can already use it at the airport.
In practice it only took a few minutes after inserting the SIM card for the first time before the data option was activated. In terms of speed I couldn't complain but the network managed to kill two different kinds of VPN tunnels regularly. It's a bit of a nuisance and I haven't experienced that in other countries before but I could live with it for a couple of days.
So while there is room for improvement I really enjoyed the freedom of having Internet access when out and about without roaming charges and it also spared me the $12.99 Wi-Fi charges the hotel wanted to charge me per day. I like competition.