Have you seen my videos of the ACE on narrow trails?
I have a RZR, and I have an ACE, and I can tell you that the ACE goes places I would not even consider in the RZR.
You're not going to have an issue keeping up with quads on narrow trails if you are an experienced trail rider.
That is actually the main reason I bought an ACE: To have the comfort of a RZR, but be able to go on the quad trails with my friends who have quads.
I know all about agonizing over a decision, even after the purchase has been made, until I can prove to myself it was a good decision.
Try to find something else to do to take your mind off of it. Build a shed in your backyard, or make that paving stone patio, or re-do the kitchen floor or something.
A forum community dedicated to Polaris Sportsman ACE side-by-side owners and enthusiasts. Come join the discussion about reviews, off roading, suspension, troubleshooting, maintenance, performance, modifications, classifieds, and more!