Go for 750.
Tho I am not sure why you wouldn't go for 750 TI, it's well worth paying extra few bucks for ti. Especially for 750 version.
The market and the consumers are more likely tend to lean on the Nvidia over Radeon, and of course, the results and reviews build those reputations for a reason.
Just go for 750 ti, and if you can maybe wait bit more to save extra dollars and buy gtx 960 for way better perfomance than 750 and still getting budget high end gaming gpu.