which snowmobile is more bang for my buck?

http://nh.craigslist.org/rvs/923106569.html

or


http://nh.craigslist.org/rvs/930742417.html

one of my friends has a 05 rev 600 HO and another has a stock 03 f7 efi. I want something that will keep up. also would i beat my friends with these? also hows the acceleration? thanks a lot!