My XA30.5 is in separate 10'x12'x8' room from my main system. I didn't have room for it in my media cabinet, and my wife didn't want it on the floor.I can keep my hands on the fins of the 30.5 comfortably for as long as I like.The fins are warm, but not hot to the point you have to worry about children touching it (like tubes).
It's one of the cooler running class A amps out there.I get more noticeable heat generation when my Dynaco ST-70 amp is running for a few hours in that same room.
That said, I live in the NY snow belt and not Arizona. Al's reasoning above is excellent. If you can handle a couple 100 watt bulbs firing away in that room without needing to crank the AC, you should be good.
If you want a similar XA30.5 sound without the class A design, the Jeff Rowland Model 2 is pretty close in sound. More delicate and finer grained. Zero heat due to it's AB design. Kind of hard to find these days though.
