Yeah, MB made one, but it has been out of production for a while. They still pop up from time to time and go for about $700 bucks. The Eggie SS4 is not produced anymore either. There are still some of those around, but you got to look for them. New, they were about $900...but a damn good product. I had one, sold it like an idiot. Bradshaw, you can find them from time to time on ebay, but he builds pretty much custom spec, so it will have custom loop control and other things built into it. Then, there's the uncertainty of getting it in the same decade you ordered it. Which, leaves the Radial Headbone. Not sure if there are any horror stories with it. Their stuff is pretty good. You just want to make sure of a few things....1) there is always a load present, 2) when switching, a load is always present when relayed from A to B, and 3) if you lose power, the load remains on the selected amp or it defaults to one of the amps without interruption. It's one thing to design a looper type box or FX pedal, but another to design a fail proof relay system with transformers and 100% redundancy in loading and seamless switching. You got a lot on the line that can lead to catastrophic failure and I am betting that this is why there are limited products on the market for this....too much liability.