Go ahead, call it a 'Race to the Bottom'. Our search for the best value in a Smart Phone plan is really a quest for the cheapest Smart Phone plan. One of the decisions made early in the process was to go with a GSM phone primarily to take advantage of all the 'Bring Your Own Phone" opportunities. After playing with the bargain-priced T-Mobile $30 for 5Gb/100 Minutes plan, I knew I needed a lot more minutes when I eventually converted to one main phone.
I was convinced that the best route was the SIMple Mobile $40 plan. Then a friend told me about her weekend in rural Colorado. You know, one of those areas where there's only Verizon and AT&T coverage. Where would that leave a SIMple Mobile phone? Unusable. They do not claim any coverage off the T-Mobile network. So much for the $40 plan.
The next move up in price is Straight Talk at $45. They claim their GSM coverage is the same whether you put their SIM in an AT&T or T-Mobile phone, locked or unlocked. After reading posts from Straight Talk users, it appears the ones who use an AT&T phone get "throttled" after using more than 2 to 3Gb a month, while users with T-Mobile phones don't have similar complaints. We'll make our decision soon and report on the results.
As a disclaimer, I notice there are numerous ads for Straight Talk service across our web sites. We are not compensated for reporting on or leaning toward that service.