Rxpert83
Dr. Feelgood
T-mobiles chat support is clueless to any of this, so I'll ask you T-mobile experts. 
Background info:
I'm currently on the Sprint network but am interested in switching to T-mobile. I want to test the network to determine if its good in my city. I currently own a nexus 5 purchased from the play store, so I can take it to whatever compatible network i please.
The hangup though is that I'll be under contract for another few months with Sprint.
I've got a T-mobile pre-paid SIM.....
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Q's:
Can I activate the T-mobile SIM on either their $30/mo plan or their pay by the day plans, test out their network as I see fit, and switch between networks on the go just by swapping SIMs and rebooting?
Will it affect my Sprint account in any way? (I won't port the number or anything like that)

Background info:
I'm currently on the Sprint network but am interested in switching to T-mobile. I want to test the network to determine if its good in my city. I currently own a nexus 5 purchased from the play store, so I can take it to whatever compatible network i please.
The hangup though is that I'll be under contract for another few months with Sprint.
I've got a T-mobile pre-paid SIM.....
----------------------------------------------------------------------------------------------------------------------------------
Q's:
Can I activate the T-mobile SIM on either their $30/mo plan or their pay by the day plans, test out their network as I see fit, and switch between networks on the go just by swapping SIMs and rebooting?
Will it affect my Sprint account in any way? (I won't port the number or anything like that)