Have decided on Megasquirt MS2 extra ECU for the Jag V6, running Semi Sequential injection and wasted spark ignition.
I don't have either COP's(4 pin) or EDIS at the moment, it will cost about the same for either system. So which would be best?

How about MS2 with coil drivers and a ford 6 cyl coilpack? That's how I'm doing my Jag.

I've just used toyota COP's with ms2 and they work well, require a couple of simple mods to the board and cost next to nothing.