Bike Forums - Am I Crazy?

So I started out MTBing again two years ago after an 8 year hiatus before that. Bought a brand new Trek 6500 (06') and rode quite a bit. Problem with the 6500 was that it didn't fit. Not sure if it was the geometry, too big/too small, etc., but it just didn't work and riding was unpleasant at most times. Fast forward to this past May, and low and behold I bought a Gary Fisher Presidio 09'. Put about 300-400 miles on it so far, and love the bike. Here's where the dilemma jumps in. I miss having a MTB! My buddies are lonely without me on the MTB trails, and I am definitely not taking my CX bike on the trails we ride. My 300lb 6' frame and a solid carbon fork + really rough trails= Teeth knocked out/sterilization. So I sent my LBS guy an email about trading the CX back in for a MTB. I have kind of settled on a Gary Fisher Rig. Say what you want about it but I really want to try a 29er and especially SS. My LBS carries Fisher, Trek, Blue so those are pretty much my choices. I figured I could get an even swap for my Presido for a Rig. The only mark my Presidio has is a scuff on the downtube. Otherwise it looks mint. Am I crazy for wanting to do this trade, and even more so, am I crazy to expect an even swap? My bike cost me $1900. A rig at MSRP is $1400. What do you guys think?