Feature:
For installation work there is tamper proof panel that you can screw onto the front. However, I am using it in my live bass rig. The power amp is rated at 200W per channel into 8 ohms but can be bridged to 560W into 8 ohms. It is also a linear (Class B in this case) amplifier and hence does not suffer from the frequency and load dependent phase shifts of Class D amps. The linear power amp combined with the high power and small size 1RU are the reasons I bought it. There is also a small fan which is probably too noisy for a quite studio environment but to me it still seems quieter than a computer fan. You could replace the fan with one by PAPST if the noise is a problem in your environment.

Quality:
This is a very inexpensive amplifier but I would still say it is pretty well made. The chassis is made of steel and the internal construction is typical of modern manufacturing. It has obviously been built to a price (everything is these days) but that being said their is nothing wrong with the construction. It contains a single sided board but the component choice is good enough and should be reliable in operation. The filtering caps are 105C types and the input opamp is a AN6554 which is a very respectable quad low noise opamp.

Value:
Considering the size, power and sound this amplifier is excellent value. I think ART have struck an incredible balance of features versus price.

Desirability:
It is a pity about the extremely bright BLUE Led that ART have incorportated into the front panel of this amp. On stage it would be shining straight into the audience and annoying everybody. You could reduce the current into the LED by making the series resistor larger as another reviewer suggested but I simply replaced the LED in mine with a 20mcd device from RS components. I think overall the unit looks pretty good but I would lose the large rounded rectangle line that encloses the power and gain controls on the front panel as well. In my opinion this thick white line makes the unit look cheap. Their are no filters on the air inlets on the power amp so if you work in dusty environment the dust will be drawn into the power amp by the cooling fan. All this aside it is still an excellent addition to my current setup.

Sound:
I have been listening it the ART SLA 2 in my Hi-Fi setup now for two days and I am quite impressed by the sound. It is pleasant to listen to if a little brittle in the treble and a bit congested in the mids. The bottom end is nice and dry but perhaps lacks a bit of weight. Their is slight buzz (very low level) that is audible when your ears are against the speakers which is probably due to the power supply filtering being a bit light on (4700uF per rail) and there are no snubbing caps on the bridge rectifier. Very detailed and engaging though.

Ease of Use:
Very easy to use. It features both TRS and XLR inputs as well as a binding strip (which they could lose in my opinion). I would like to have four pole speakon connector

Support:
I hope obtain a service schematic for this amplifier but I haven't tried as yet so I can't make a call on this as yet.

Overall:
This amplifier is a bargain considering its size, power and performance. I do not know of another linear power amp of this rating, in this size, without resorting to the dreaded Class D amps which abound at the moment.