The GX 5 is a very competitively priced budget amplifier from QSC.
The build quality is exactly what you would expect from QSC, despite the budget price point it doesn't feel cheap at all, the rear connectors are nice and solid and the case feels strong and firm, no flimsy, bending cheap metal as you pick it up.
The gain knobs on the front also feel nice and solid.
Well featured inputs, been aimed at the Mi market it's got phono as well as balanced XLR/Jack, the phono's are a great for connecting up a phone or mp3 player for quickly testing speakers (without getting out a mixer etc) or just for basic ipod disco applications.
Sound quality is very good for the price point as is the power output, works well and does what it says on the tin!
My only negative comment (if I have to find one) is the weight, been a conventional transformer power supply, rather than a switch mode supply, but something has to give at this price point.
All in all a great budget amplifier, QSC quality!