I've decided I want to get a trek 29er but can't decide on a price point. I've decided that I want at least a Marlin for the lockout on the fork. I don't know how deep I'll delve into offroad riding, but I have a feeling that once I start I'll want to do more. I have a few trails nearby but I've never ridden them, but my LBS recommended a Marlin, or a Mamba for something more sturdy and nicer. I've also looked online at the Cobia and X-Cal. They all look to have the same frame, except the chainstays on the higher end have a different dropout. I think if I really wanted to I could save for an X-Cal but I figured its probably above what I need and the bike will get plenty of road / paved trail miles on it. I don't know what my LBS is asking for Cobia and X-Cal, but are they in a different league than the Mamba and Marlin that it wouldn't make sense to buy for recreational riding? As I said, I thino I could save for a +$1000 bike, but I do want to own a mountain bike this summer. So I was wondering if anyone thought might be able to help suggest where to draw that fine line. I originally just was going to get a Marlin and be done with it, but I got to thinking maybe I should spend a little more now than later. I think the biggest difference between each model is the fork, and then just higher level components with almost identical gearing. I'm open to all suggestions, hank you.