The low speed needle adjustment is a pain to do but once set, it will make all the difference in the world. It also helps tremendously with the transition between mid-range, where most of us operate the engine while in flight. We don't usually run wide open throttle for the entire tank of fuel, you probably run half throttle most of the time so this adjustment, once right, it really improves this mid range run as well as the idle and transition from low to high speed.

DS.