I would recommend against that power supply, heres a similarly priced one that is much better
http://pcpartpicker.com/product/N6X2FT/evga-power-supply-220gs0550v1
Also, if you can wait till the end of the month when the rx 480 comes out, that will be a MUCH better deal for your gpu.
looks like a good build though, everything you have there will work if you decide not to make any changes.