Just got the 4 button footswitch for my Mustang III v2 amp. User-configurable as I understand it. My biggest concern was that the buttons were too close together, but I need not have hesitated. As long as I don't use the middle of my foot all the time, it's no problem. I still don't know how to use it fully, but the idea is to slowly re-train myself to see if I can bond with it enough to replace my simple pedal board. Will still keep the volume pedal though, but it is a passive-type so I can do away with lugging around a 9v power supply and the extra wirings. What took me by surprise is that the cable for this footswitch is just a simple mono-jack lead (I expected a multi-wire connector considering all the functions it can do). The biggest drawcard for me is the LED digital floor-display that shows which channel (pre-set) I'm on. I usually play away from the amp, and it's a pain to keep coming back to the amp to take a peek at the LCD screen (great for menu-diving when making presets, but not so great when playing in the dark). I do have the 2-button Mustang footswitch and could plug that in as well to get 6 footswitching combinations, but I think I see if I can make do with just the MS4 to keep things simple. The idea is to simplify things as much as possible without missing out on the floor switchable effects that I need. - If other MS4 footswitch users out there have set-up tips - and would like to share specific configurations that are especially useful, I'm all ears.