I take it you like the GX5?
Yep. For the price (I paid $350 on sale!) I can't complain one bit. Now, if price is removed from the equation, it has issues when compared to audiophile amps, no doubt about it. First the positives: QSC makes tons of amps (like Crown et al) so you know they have the knowledge to build a solid amp - hence the 6 year warranty on an amp designed for outdoor (i.e., loud) use. QSC even has some THX certified Cinema amps, only useful in knowing that the worlds of pro and audiophile are not different in terms of what sounds good.
Also, the GX5 has RCA inputs built in so you don't need RCA to XLR converters as with so many pro amps. I had a Crown first and returned it, and did no like the $10 converter I used. The GX5 plugs right in, no issues. And, this thing can run 700 watts to a 4 ohm load all day. I have never seen the clip light illuminate and I have run the snot out of this amp in 2 ch mode. Also, as the QSC website explains, the GX5 (but not GX3) uses the dual rail technology of its big brothers (PLX series I think). In short, when just humming along for TV, etc, it uses a low power rail that makes no heat. When you flog the horses it switches to the high current rail and then needs a fan to cool it as it does not have much of a heat sink - but that also makes the package small.
Now, the buyer beware issues: (1) the internal fan is loud and must be removed for HT use - IMHO. The removal takes 10 minutes. I then mounted that fan and another on the exterior side exhaust and heat is no problem, and the fan(s) is quiet once out of the case - cheap internal mount vibrates causing the problem. Removal allows the air to flow inside as the fan is mounted mid-ship so if off it blocks air flow. (2) No remote turn on trigger, so you gotta flip the front panel power button on/off. (3) The power light is like a damn blue laser that is distracting. Cured with the blue flashing light from a $5 Lego set (yes, a child's toy). Fits snug on top of the light, no mod needed, and makes a pleasant pink glow, no laser show. (4) Industrial look may or may not work for you. But better looking than many pro amps.
The Crown I had (XTi ???) had a noise floor that was too high. The GX5 had the best S/N ratios in this price range. Check the S/N ratios, some get real high. If not for the QSC sounding so good I would have tried the Yamaha next as it has a nice look and good power, with low noise.
Considering I paid $300 for my Harmony remote, this was a steal at $350. For what it is worth, I saw a QSC PL? series at a pawn shop for $300. The point being, the pro amp market is much more fluid than the audiophile market, so check for used band equipment if you want a real deal.
