Mountain Bike - Disc Brakes or Linear Brakes?

Performance is greatly enhanced with hydraulic brakes, but that's only half the answer. If you are doing real off road stuff, a bent rim is always a potential problem. Discs will work with a bent rim, and rim brakes may not. That's the real benefit. The price of mechanical discs is about the same as rim brakes, and you get them automatically on most mtn bikes these days anyway. Rim brakes come on cheaper bikes. It's really about what you want to spend on a bike, not on brakes. If you lower the price you step down an all the components, not just the brakes. Cheaper derailleurs, cranks, wheels, frame, bearings, etc. Don't short change yourself or you'll regret it later.