Singlespeeding is hard

I've had the single speed as my only mountain bike for 2 years now and I'm getting tired. I still love the bike but a shiny new geared bike is in my future. The ride from my new house to the trails is only a few miles but the singlespeed makes it take longer than it should. I just put my Range Rover on craigslist to not have a gas hungry suv and that will give me some cash for the new bike. I'm thinking of getting the Gary Fisher HiFi Pro 29 or building up a Pivot 429. Either bike will probably work great for the Colorado trails.