i've been using clay's multijamma for years without issue, but i'm only running three connectors... smashtv, total carnage, and a j-pac(mame), works perfect, heat isn't an issue (even with a pc)... i have a pc power supply for the pc, and one for the multijamma/smashtv/totalcarnage...
the ide cables work out, the hard mounted jamma connectors on the 6-in-1 seems like a terrible way to mount a bunch of different jamma boards
if i were designing one, it would have 8 (or 20 or whatever) full wired jamma harnesses (and a dangling kick harness that could handle trackball inputs etc) wired to the switcher (or with a connector and you could have varying lengths)
then the switcher has one button, where you cycle through like the multijamma, but only power the board that you're using, and the next board or two in sequence... then you could have lots of boards connected without increasing the load/heat (maybe also two directional buttons through the list, so a forward and back, keeping the next and last games powered for quick running
or alternately an input for each game that goes directly to it, but then you'd need an optional "power all boards" or "power on selection"... you could incorporate the buttons for each game into the artwork on the cpo or bezel so games could be picked easily without sorting through a list
- gwarble