I first had one of these units when I used a Roland JC-120 as a powered 2x12" speaker cab. Dirt pedals going into one of those cute little EHX 2ube preamps, some delays going out in stereo to the Reflex and then two feeds going into the JC-120 power amps. Back then I also had an Alesis Quadraverb, VanAmps Sole-Mate, and a lovely old solid state Laney reverb unit.
Going short spring reverb (Sole-Mate into the long-spring Laney = complete reverb win.
But what about the Reflex?
It's really good. It's not got the sparkly character of the Quadraverb, it's a bit more neutral than that. The reverbs and effects really suit guitar and it's very easy to dial in.
Prices vary, anything from £40 to £80.