Mountain Biking - New to off road, narrowed down to 2 bikes. Please help!

Hi I am going to try this off road thing this year. I currently have two road bikes (a Specialized 07 Sirrus Sport, and a 08 Transition Comp), so this new bike will be strictly trail riding. I am a bigger guy (6'3" 280lbs) and have no off road experience at all. I was at the LBS and narrowed it down to two bikes.
1. Specialized Rockhopper Expert Disk 29
2 Specialized Stumpjumper FSR Expert 29
The Rockhopper is brand new and I can buy it for $1199, while the Stumpjumper is a demo in very good shapewhich I can buy for $1899. Obviously the Stumpjumper is the better deal (and that is really the only reason I am considering it). I am looking for advise on the pros and cons of both. Is there any reason I would be unhappy with either, or three months down the road wish I had bought the other bike? Is this a no brainer and the Stumpjumper is definatly worth an extra $700? I'd hate to pass on this deal and kick myself in a couple of months for not taking advantage of it. On the other hand I dont want to buy a bike that may not be the best for me just because it was a good deal.
Thanks

You will not regret the FSR. That's a killer deal.

Yea, it's a good deal, but will he like the way a FS rides? I went from a HT to FS, and now I looking to go right back to a HT. I just didn't like the way the rear shock felt. So yeah, it really all depends on what you like.

If you are coming from road bikes, you may not like the feel of a full suspension. If it is a demo bike, can you actually try it out on trails to see if you like it?

Well can't say for sure if you'll like the DS. I was given a trek liquid to ride for 2 weeks, did'nt care for it much. However, It had some realy nice componets. I thought I'de love it, but not worth the money and energy. They have their place, but unless you hittin some steep drops I wouln'd bother.

^^^+1^^^, I would go with a HT if I were you, or like someone else mentioned see if you can demo a FS, and see how you like it.