Since you DO have the Pro, you could get away with up to 130 mm of travel without changing the feeling too much.
I have a 2001 Psylo and it's a great fork. I wore out my bushings, and I understand they've improved the durability on newer models.
Personally I didn't change mine out because I ended up buying a Marz. Z1. I feel the Marz is a much better fork all around.
I put the Psylo on my SS project bike.
Also, if you weigh over 200 lbs, I highly recommend the 20 mm through axle option! It helps reduce the lateral flex significantly.
I will probably not go back to a standard dropout fork, unless I loose 75 lbs. (Not likely!)
L8R
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