I"m using a 800 P.Q. and with all the time on them i think you are right,can really notice the difference compared to the old ones.i think i will try the hacker combo with he airfoilz edge,is the 20L the way to go with the airfoilz since it is a bit lighter then the Stiffy?and i see a wide range of batteries listed from 1320 on up for it ,what have you found is the best for flight time,weight ect? Olin