If a nikki beats a jug from an even start then the jug driver messed up. that doesnt mean the jug will always win...but he will control the fight. Once the fight is above 12k or so it favors the jug even more...
Normally when I hear this "I always win" we're dealing more with picking vs actual ACM. Run into bluekitty, Greebo, Wadke, Fx1 or a host of others and I dont care what your in (or for that matter what i'm in) and you will have your hands full. Personally I find thre nikki to be a marginal threat in anything but the best hands. Ki-84 and even the ki-61 are much more dangerous rides....