Gen 1 or Gen II? Standard springs?
Assuming you're average weight and not the last of the great late brakers, you could probably benefit from slightly less viscous oil to improve the high speed damping reaction. Or in other words, make it a bit less choppy on rougher roads.
I used 5w Silkolene RSF when I had stock forks and springs in mine.
Confusingly, the viscosity index numbers quoted for fork oils aren't consistent like engine oil ratings, meaning that some 5w oils will be thicker than others and so on for other viscosities.