Mountain Biking - Specialized Stumpjumper vs Trek 6500 vs new Windsor 4500 4700

So, I'm typically a fixie/road rider but thought about getting a mountain bike for some fun on the trails around here... As such, I don't want to spend a boat load for a new bike, and went the craigslist/bikesdirect route...

I see a couple options - one is a stock Specialized Stumpjumper circa 2000 for like $250, a Trek 6500 with Manitou fork, XT components, and "new Vuelta" wheelset for $350 vs the brand new Bikesdirect Windsor or other frame with Dart 2 and mixed deore/alivio components plus disk brakes.

I am decent at fixing bikes and have no problem getting a used or bikes direct bike. My choice would be dominated by weight since I come from a road environment where weight is often very important, and of course fun on the trail. If I end up using a lot, I can always upgrade the bike down the road. My single speed with 24in kevlar tires has seen 400 days of riding of the last 450 days, despite snow, salt and grime in the North East... and it's only a Motobecane Messenger... with no further tune ups and upgrades outside of regular maintenance and assembly performed by me...

Any input will be greatly appreciated - thanks in advance - I'm gonna check the Stumpjumper tomorrow since it's local - may pull the trigger if I like it and it fits... Hope to negotiate $200... Reviews always says that Stumpjumpers tend to be lightweight bikes that are much fun...

Stumpjumper
http://images.craigslist.org/3n33kf3p55V25Z55W6acrd35b2663bbdc162d.jpg
Trek
http://images.craigslist.org/3n13ka3m35V25U35P5acu484482f132b917ae.jpg

The trek looks like an 06 model. I'd opt for that one if it's in good shape and fits correctly. As with everything on craigslist... offer less

I've purchased a few used MTBs. IMHO, the one component you have to check out carefully is the shock. Replacing it can kill an otherwise good deal. I've been there on both sides of that problem. I really like Specialized and the Stumpy is a light bike, but if it has the original Manitou SX fork, you'd better be sure it's working perfectly because finding parts for that thing, especially seals, is very hard. Manitou does not support those forks. It's a shame, they're pretty nice for a lower end fork. Ihave two and both leak. The Trek has a Manitou Axle Elite, same fork I had on my Rockhopper and very similar to the fork that came originally on my FSR XC. I like the Axle, it performs well with good rebound control in it's price range, but it is heavy (around 5lbs). As long as you know that, you should be good. Some have critisized the Axle for being soft. I've never felt that way about mine including when I used to weigh in at 220lbs. I believe you can still get parts for that fork. I had a slightly older 4500 and a 4300 that I used on MUPS. They were nice bikes. If the 4500 had been a larger frame I probably would still have it. I can't comment on the Windsor one way or the other. I'd tend to go with DirtPedalerB's recommendation if it fits you well. But if you don't mind looking at a replacement fork down the road, the Stumpy may be the way to go.
One thing I like about used bikes and why I like to go with them. If you don't like it, you can usually flip it for close to what you paid for it. That won't be true with the Windsor.

So, after some deliberation, I went with the Stumpjumper... It's the Specialized Stumpjumper M2 Comp, XT front, XTR rear... The forks were actually reportedly changed recently - the bike has the Marzocchi MZ Comp - from browsing it seems a cheap entry level fork... which is OK for now while I get into it, and I can always upgrade as I overgrow the fork... I'm looking at XC with some stump jumping...

The Trek was an hour away, and for some reason, browsing, Specialized seemed to have a better overall reputation...

As I brought it home, and we still have some of the snow banks around - I took it down to the park and had it climb over the ice boulders - It's a fun little bike. Derailleurs need adjustment and the bike needs an overall tune up which I will attempt this weekend.

Is it worth trying to disassemble the forks for cleanup? Supposedly this forks do not use oil, so wouldn't really have anything to change... I'll get some pictures over the weekend.

What's your opinion on the MZ Comp?

Good choice based on the replacement of the fork. I can't comment on the Marzocchi other than that is a well respected brand, even their entry level stuff. You should make one other measurement, check your chain. The Sheldon Brown website has a very good way to measure chain wear using a ruler. The chain is the first item I check when I buy a used bike. If in doubt, replace it. I like your idea about riding it with the existing fork. If it's just a spring fork, I would not take it apart. I only service air forks or oil rebound spring forks. Just my opinion.

I'm glad you will be stumpjumping with your stumpjumper :)