Well I finally took the plunge, ditched Sprint for T-Mobile and I am very pleased with the service I am getting. My dl speeds on T-Mobile are 4 times faster than Sprint. I could never get LTE at my house with Sprint (GS3) and I have constant 4g at home now.
When I called Sprint about cancelling the service rep was quite amusing, he told me that T-Mobile would lock me in a two year contact

, there are so many towers in my area being back hauled (bs line for the past 2 years) and T-Mobile's coverage would be terrible.
Well worth the cancellation fee which was only 160 and I will make that up by selling my S3 on Ebay. Wifi calling is a nice bonus as well, loving this phone and this network.