don't worry about drivetrain components, they're easy to break and at that price point, you shouldn't really be comparing them at all. big manufacturers are watching each others' bike lines and most of the time, there's a reason why one is more or less expensive than the other. for example, norco's freeride hardtails come with really low end drivetrain components for the price, but they have above-average cranks, brakes and forks for their category. that stems from their philosophy that drivetrains are easily broken esp. with freeriding and you get better brakes and other longer-lasting components for your money.
one mistake i made when buying my first mtb a couple of years ago was being set on a certain drivetrain part. there's really not much of a difference between say, alivio and deore. just focus on which frame geo you like best. also, brakes tested at the lbs may vary a lot, because brake pads usually have to be broken in.