What's my reasoning again for not getting Virgin Mobile at $35/month?
I will use voice very minimally. Text not so much and really only use the web for browsing, google maps (GPS), email.
VM (Sprint) 3G data speed is pretty slow compared to TMO, HOWEVER it is all very dependant on your location. It would be best to find people in your area who have both to compare what the service is like in your area.
One other plus about TMO plan is that you can BYOD, so it is a bit more flexible.