My updates on my updates! I now have both phones working just fine on a new prepaid TMO plan. I wanted to eliminate any possible variable with my Metro account. Cutting to the chase, the problems on TWO 925's seem to be due to bad phone/SIM contacts. Yup, simple as that. The longer version, as I told my brother:
Thinking about sudden phone loss, failure, and Metro being unable to just swap a SIM policy, ("Be prepared! It's the Boy Scout marching song...") I decided to set up a new TM account as backup. Could forward Metro number to it in the short haul. New plan: only $3/mo, which includes 30 minutes of talk or text, no data. Over 30 minutes, eaten up as 10 cents/min. Data can be added separately on daily, weekly, monthly plans, but hey, that's why the goddess made wifi.
At the TM store, we set this up and installed the new SIM into 925B.......and nothing happened. "No service." Same old ****. OK, a bad phone. But for the amount of money, I kept the plan.
I came home. The new TM SIM worked fine in my 810. And then, it started working in 925B, too! But it dropped many times per hour to "No Service," even as the bars pretty well tracked with my 810. My conclusion: the 925 isn't any 810 on the radio side. Worse than your LG!
When I put the new SIM into 925A, the one that refused to "see" any SIM, ever, it started working! When I tested with an AT&T SIM, it asked for the unlock code, as it should.
So, back to 925B again, with it's frequent dropped signals. It's now fine.
Conclusion: ****ty phone/SIM contacts endemic to the model. Frequent insertion and removal of SIM's took care of corrosion.
I guess I'll go to the Metro store tomorrow and register the 925B with them.