I have 3 Naza Lites flying now. (1 550 hex, 1 "Flip" quad from ready to fly quads, and 1 Gaui 350X quad. I love em, especially considering the price. They ain't for aerobatics, but are very stable, and very easy to setup. I just ordered a third Gaui 350X from Amazon, whole she-bang, quad, motors, ESC's, and Naza Lite w/GPS, for $300 and free shipping! Best price I've found for just the Naza Lite w/GPS, is $169. BTW, the lil Gaui's fly nice!
Here's my first Gaui kit, "BEFORE" I hooked up the GPS, VERY stable, no tweaking or farting around with settings etc.
https://www.youtube.com/watch?v=_ZlCcC6yu4k