to me it sounds like that your swashplate is not level, becuase it should drift to the left but not violently. so check your swashplate to makesure it's level, center the servos, and makes sure that 1/2' goes out on top of the swash plate, check out bladecprepairs.com for more info. also, when you throttle it up slowly, dont let it drift away, stop the drifting immediately when you notice it, and keep adding throttle, do both things AT THE SAME TIME. so as you increase throttle, keep the heli in one place and dont let it drift if at all possible. i can take off and land vertically with my blade cp, i got the bh and lipo and cf blades, so it's no difference than a bcpp with cf blades. i'd say check your swash plate, and add aileron as you throttle up, it should take off pretty straight if not vertical. the more you do it, the more natural it'll become, and you wont even think about it after a while.