I have had 4 mark 3 golfs 2 x 8 valvers and 2 16 valves
bought 1 x 16v that had decat was loud as hell but no real benifit even though chipped
cammed and remapped ecu
I decatted 1 x 8v and it just added noise and definately lost its low rev torque
I would definately avoid decat unless you have seriously modded the engine as it does very little to power on 8 valve all it does is switch from low down torque to higher in rev range.
16v sounded nice but again no benefit bear in mind these cars run the same engines as
mk2 ibiza