Many people use the RMX line as well like me(RMX1850HD) and no problem at all in home environement,many people use the cheap Behringer EP2500 that is suppose to be a cheaper ripoff of the RMX2450 without problem. I also own a QSC MX3000A for my subs,a QSC 1080, a QSC USA370 bridged for my center channel,2 Bryston's 4B and a Crown XLS402B no issue. IF you check at QSC forum you will also find that Bob said the RMX should sound really close to the PLX serie, yes the PLX are really nice but i would never say do not buy the RMX,MX and USA line are really good and tough amps.
The main problem is the noise comming from the fan that can easily fix with a low noise fan installation[].