They are equal, get whichever is the best model for the best price. Also get whichever will work with current or future display you plan to get, freesync or gsync.
If possible try to hold off. Neither option is great right now. These cards are already basically over 2 years old and new models should have been out by now. Right now they both sell good models for tight at 200$-210$ which is a little better since at launch they were around 250ish.
I go with AMD because I don't like Nvidia as a company, they almost remind me of Intel or apple, but not as bad.