The build quality is very good, the interior is split into two parts separated by a huge radiator, there's no chance it can overheat!
It's a pretty powerful amp that can deliver quite a bit of watts to four speakers over two channels. This means it can feed two speakers on the right and two speakers on the left. I don't have the features at hand but, besides the comfortable power, it has a very low distortion rate, although the specs published by the manufacturers are often false.
In use, the A-R600 reveals itself as a standard hi-fi amp featuring two big potentiometers, one to select the source, and another one for the volume. But be careful with the volume control, it is graduated as attenuator, so everybody gets it wrong the first time. The three knobs in the center are to adjust the bass, treble and balance. Do note the presence of a slim "source direct" backlit button.
The sound, which is what matters most when it comes to an amp, is the A-R600's main strength. It has an impressive dynamic response, the highs are precise, just like the lows (something pretty rare on hi-fi amps), which aren't muddy nor soft. On the other hand, this amp adds quite some coloration. The bass-treble controls are trivial for home studio use, as well as the loudness button, because they don't allow you to grasp the coherence of a mix, not to mention the coloration they add, which isn't really a defect in itself once you are used to it, it's a smooth coloration that produces a very analog, high-end hi-fi sound. But to mix down it's sometimes useful to engage the "source direct" function, in which case the sound transforms and becomes much more precise, less rock and more clinical. Both uses are complementary at first, but once you grow used to it, you can achieve very good things without resorting to this function.
You can't really talk about value for money without talking about durability. Nothing has changed in the time I've had it, except maybe for the washed-out paint on a button, but the sound remains the same.
So, I recommend it to anyone looking for a precise and powerful sound to listen to music coupled with some good speakers. It's a very good solution, maybe a bit too powerful. Personally, I have never cranked it beyond a quarter of the way, otherwise I could damage my ears. I give it 8 due to some minor details, like the binding posts, the paint and the power, which isn't really optimal for home studio use.