I would NOT mix the U4.4 with pump gas, for that matter any oxygenated fuel with pump gas, you could mix c-12 or c-16 with decent results. oxygenated fuels can and do make more hp, will you notice a difference, maybe. VP does have some claims that you can get pretty significant gains with some of their fuels but at over $25 per gallon they are not for trail riding, either deep pockets or serious competition.
So to answer your question, I'll ask a question, why do you want to run expensive gasoline, are you going to race? or just play ride. if just to play ride save your money, 4.4 is expensive to