These days nearly everything a HAM needs can be bought - all working (we would like to believe) perfect, no need to think and work if you have enough money... For some equipment it is hard to be competitive, but I would feel shame when I buy things like elbug, transceiver audio interface,... - such things can be built at home with minimum effort and match exactly to my particular need.
Multiswitch is something that integrates a simple elbug (modified ETM5C design, my favorite...) with selector for 3 transceivers, audio interface to connect computer sound card or PTC2e controller to HF transceiver to operate digital modes (possibility to switch between 2 radios), CW computer keying interface for LPT port, FSK keying interface for COM port for RTTY operation (less QRM to others than sound card interface) and buttons used to switch mains power to shack on and off.
It is stupid simple desing, nothing more to say. So you can find here just the circuit diagram (perhaps someone can be interested) but no PCB etc. You can find the panel on the picture just bellow the rotator control unit.