I'm pretty sure if you took an ED30 around a track and an R32 around the track, the ED30 would be quicker.
R32s are only 4WD when you don't need FWD - I think you have it confused. Haldex is an electrically controlled hydraulic multi-plate clutch unit which only, and only, sends power to the rear wheels when the ESP/ABS system notices a difference in rotational speed between the front and rear axles.
That's why if you have Haldex it's VERY important you don't mess up the rotational diameter of the front and rear wheels, otherwise you will cook the clutches/hydraulic fluid as they are not designed to be used the whole time.
I mean ultimately the only benefit the R32 has to me is the noise! Which is very nice.
It's more expensive to run, service, drive, and in the real world unless it's sopping wet, don't much faster!
Anyway as per all the "WHAT DO I DO CAR WISE" threads that normally wind me up, try both and decide for yourself... as it's your money.