just to clarify, as I work for sprint currently:
Updating your PRL does nothing, other than tell the phone which towers have lower roaming costs. (on sprint)
Verizon doesn't roam on any network. (I was a verizon manager as well) If you have a vzw phone, you won't roam at all.
If your using 109 gb's a month and complaining about sprint saying something to you, I would reccommend getting an actual home internet connection instead of using it for tethering so much.
As far as the roaming stuff, yes, if you roam a ton while with sprint, they can release you from the contract, but its not an automatic thing. A lot of times you will have to call cs a few times (because sprint CS sucks, and are a bunch of morons usually) and have them pull the account and see how much you are roaming and how many dropped calls, ect, are.