my old valver was still going as good as ever on 136k
my 8v has done 160k and is one of the quickest standard 8vs ive driven
my mates 8v is on 180k and that still pulls pretty well although we have ripped that out and are fitting a 2.0 in there
As mentioned though its best to buy a mk2 on its general condition, not the mileage
Worry about the body, not the engine