Does anybody have experience with Source Audio Soleman, see here? It is quite pricy, but seems to bring a lot of possibilities for programming.
No experience with it, but there is a lot of flexibility for a 4-button controller.
I think you would need to be prepared to do a lot of setup in the editor app though 
I’m curious what a good workflow would be with this. For example, could you comfortably move between a preset/scene mode and the panel mode (thinking here that each panel would be used for particular effects). But it could quite quickly become a tap dance.
Unless you particularly like the small form factor, my preference is always the larger ones with more switches.
Do you have this setup on your rig?
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