I personally think that ART once designed and manufactured innovative multi-FX processors. Nowadays, with newer ADA converters there are many other units having "more transparent" sounds, but I'm a big fan of them.
By the way, I have a SGX-Nitro which is a much more complete multiFX unit, from compression, distortion, expander, noise gate, graph EQ, freq filters, phaser, chorus, delay, reverb, pitch-shifter, acoustic simulator, and some others I now forget. It's in my rack in pristine condition without seeing much use as I've slimmed down my set-up considerably and it hasn't been used at all lately. If interested, send me an email or PM and I'll give you a good price.
I had an ART FXR years ago - piece of junk, really.... you have no control over any of the parameters, and the reverbs are very harsh and metallic-sounding (much like Behringers reverbs sound like today!)
Don't bother with it... Today's budget Lexicons outperform those old units by a significant margin....!