I'm looking at the comp disc version. This would mainly be for trail riding and racing.

I'm coming off of a trek 930 from roughly 10 years ago. Therefore I'm extremely used to hardtails which is why the brain on the Epic seems so nice.

Does anyone have any experience with this bike?

Would I need to upgrade anything off of the stock version?

Check it out here

the epic is pretty much one of the best xc race bikes out there. highly recommended, with the brain the bike is almost as stiff as a hardtail, but still able to absorb bumps

It's not just a race bike. I've had mine for a few years and ride it general XC for the most part. I've also ridden it out in Moab and wherever I ride. The brain is a great function and if you'll be doing mostly cross country and racing, it sounds like a great way to go.

If I was living in Moab, I'd get an Enduro or something along those lines. For now, I'm content with my Epic and can recommend it without hesitation.

I ride an 06 Epic comp. Love it. It's a stiff ride compared to my old NRS, but for my riding style and terrain I find it perfect. I've done a few upgrades to mine but they were just for personal preference, rather than absolutely needed. I'd still suggest a long test ride.

Looking at the specs I'd say you might want to upgrade the derailleurs, shifter, crank, cassette, and chain. I say that only because you say you're talking about racing it and you could save some weight. If you're only going to ride trails I think you're good to go.

There is a certain person who would KILL me if I spent 3000 on a bike, it was a close call at 800. Maybe someday.