I have a 03 999 base that I'm wanting to put a termignoni system on. The full systems are expensive and I'm happy with sound alone so I think the half system may be the way to go for me. Perhaps it will retain more low and mid range with the half system.
Anyway, I found a used half system for sale sale off an 04 999s. Does the half system fit a base 999? I'd imagine the ECU won't work because it raises the redline 1000 rpm which you probably don't want to do on the base engine. So maybe a pcIII and the half system will work?