I just did a survey of AS North in the XFR and it's absolutely ideal for a two-hours race. 3 Good overtaking-occasions and very technical parts. I think the added fun of that track is well worth the 2 hours race.
Westhill standard is only 15 minutes shorter, yet one of the most boring tracks LFS has to offer while being very dangerous due to the danger of running unto grass. Westhill Rev is a bit more fun because of T1 and the double-S, but still pretty boring. Also I already did a We Rev 60 lapper GP
.
So it's either As North or Ky Nat for me.
Before commenting on As North make sure you drove that combination.
[Edit]
@th84:
As North doesn't do the As Nat-part except the two As Cadet U-turns. It goes into the reversed As GP/Hist part on the hairpin until Eau Rouge.
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Vain