considering porting to tmobile
Since you already have sprint phones, i would suggest signing up for a RingPlus plan at ringplus.net
They use the Sprint network and your Sprint phones are compatible with them. They offer legit free cell phone service, and the rest you can read about at social.ringplus.net (thats where they post their flash promos as well).. They just had a promo for free 8000 min / 8000 text / 8GB LTE data / 200 MMS which was amazing but unfortunately i was too late to the promo and it was in high demand.
Check it out, though. Worth it since you already have an eligible device