I don't know about that stuff. I do know that, for some time now, none of the carriers would activate any analog phones. I have a friend who has an old bag phone and goes into rural areas where there are weaker signals and he needs the stronger power but they wouldn't help him. The newspaper had a piece on this; people out west in wide open spaces aren't happy.
Regarding the original poster's concerns, it's sadly nothing new with cellular companies to be a pain to their customers. I knew someone who got a cell phone that wouldn't work in his own house and he wanted to cancel his deal but they refused; he had to threaten litigation (actually get the paperwork from court) before they'd let him go. Other companies had frequent disconnects while talking.
Batteries have a limited life span. Batteries and accessories are very hard to find since they don't want you keeping old phones; I guess they want the profit of selling you a new phone or having you make use of the newest features which are a cost. Many fathers have screamed over the text-messaging bill their kids have run up.
For myself, I've tried buying batteries at yard sales, but they're usually no good; so I generally just use the phone in the car where I have the adapter. I get about 15 minutes of time out of a battery so I can use it for limited stuff and that's been helpful.
I don't think the phones themselves are built very well and probably would just break from normal handling after a couple of years.
I do not like cell phone sales people.
I know some people use pay-as-you-go cell phones but they have dirty tricks (purchased time expires monthly even if you don't use it), and the companies don't treat those subscribers very well.
Supposedly competition is supposed to make it good, but all the carriers have sunk to a lousy level which is now the base.
My impression is they want every subscriber on the $40 minimum plan.
My plan is now $20 and I suspect fairly soon they'll cancel me and force me to upgrade. I doubt it's for technical reasons, but rather they want $40 from me too every month and hopefully I'll use premo features and pay even more.