I’ve got the Studio Quad 4 and really like it. The reverbs really aren’t that impressive (but my Roland RSP-550 more than makes up for it, another great multieffects unit that sells for peanuts now), but the delays and modulation effects are quite interesting, and if nothing else there a really cool reverse effect I keep it for (Rewind This is the name, I think). Great little FX unit for what they sell for now.