elctronic help plz

[gtv]

Hi folks, just going to start building my first quad, I have a frame on order and its 600mm span but I am not sure what flight control/ motors to put on it? on a budget and going to run it on 3s 2400lipo.
I was looking at this MultiWii PRO Flight Controller w/MTK GPS Module, what are peoples views? what do I gain with the GPS RTH ect?

Many thanks for any help you can give a NOOB