I have used google fi , visable , and cricket.
For best results make sure you are using their apn’s.
For troubleshooting I also always use the real carriers t-mobile , verizon, att, in the same areas I’m testing.
You will get throttled on cricket, google fi is pay by the gb, and visable generally caps you at 5mbps.
Tho all of them have been more lax lately likely due to covid-19.
Google fi specifically has data only sims, and they work great. With visable and cricket YMMV.
Also had good luck with ultra.me, good plan , good price, they are a mvno of t-mobile.