For the pretty good sport flyer who wants to step up to precision aerobatics, I've found that this business of high resolution servo set-up with low slop linkage is an absolutely essential step toward improving the model's good behavior. With this kind of set-up, plus a decent powerplant, judicious trimming & mixing, all you need is time on the sticks. If you haven't already done so, check out nsrca.org for links to some great pattern websites.