Plus the smf for the 6spd is crazy money (at least over here), you're talking about £1000! Nice box though, nice gear changes. A friend has the 6spd in his gt tdi. My previous car was the seat cordoba which is where the smf came from, it was only at around 2000 rpm at 80 mph, shame the golf isn't like that and actually feels like it could do with a 6th gear. On the other hand I find the golf to be a lot quieter overall though so that's a bonus.
Anyway where's your revs at if you're doing 80mph with the altered 5th gear?