I work for an MSP (Managed Service Provider) in the IT space. I actually have AT&T (work demo unit) and a T-mobile 5G hotspot on my boat. Connected to a VeloCloud SD-WAN device. We spent multiple weeks (7-10 day stretches) just bouncing around the islands last summer. All the way up into Succia and I had GREAT reception. I monitored both connections constantly to see how they were performing. AT&T was decent but Tmobile was pretty much everywhere!!!
If you look closely in the pics, you can see my speeds. Top 2 are
Tmobile -
~186M download
~6M upload
AT&T -
~10 download
~5M upload
In one of the other pics, I am on an all company video conference call. Regular "hard-wired" desk phone as well... My fiance is in the salon, also working and doing video conferences... NO ISSUES ANYWHERE!!!
***sidenote***
I am also using a commercial grade SD-WAN appliance that aggregates the 2 signals as well as improves the quality of those connects (forward error correction, jitter buffering, etc.).
Doesn't effect the actual signal strength, but does allow for a "cleaner more stable connection" for us to both be working REALLY remotely!
Also, if anyone would like some advice or like a similar setup, let me know, I'd be happy to help!!!