they're not lighter than a mk4, the info on parkers is wrong. There are a few differences management/sensor wise between the 210 and 225 but both are K04.
don't get me started on drivetrain losses
its really not as simple as applying a factor to a dyno figure or even measuring coast-down losses when it comes to haldex systems.
ok, say you were running a standard 225bhp, with a 0-60 of 6.6, a map will see 265-270, and a 0-60 should potentially be in the high 5's/very low 6's... top end acceleration gains won't be as good as a FWD due to transmission loss. So all in all,
Seat Cupra R, FWD, or Audi S3 4WD... what would you have and why, both same power, just difference in transmission... Audi would be quicker off the line as FWD struggle to put power down?