If you're not going to use the car for "tracks or anything like that" then upgrading from one to two pot rears is fairly pointless from a performance and $$-out-of-the-wallet perspective.
The only good reason for doing it in
your case would be to improve the 'look' (and hint: not many people are looking at your fully sick rear callipers
).
That said, it could 'future proof' the car when selling it to someone else, as the performance upgrades you're planning are something that someone could enjoy on the track (and you should be too
