I know this is a bit of a cop-out, but I'd have to go with the first volume of "Evolution Is Timing". It has a cross-section of all of the best shows in the best quality. I could take it with me to a desert island and be just fine.
I was really hoping for some more '77 and '80 releases from Moonchild. I have all of the '75 shows now, and I want to add some more soundboards that I can't afford the EV pressings of.