I have not seen a better airmass vario system than the Butterfly. Most importantly to me, its wind solutions are amazingly good. It has been a game-changer for many in the Tehachapi-Southern Sierra tribe. The location of convergence lines is critical to X-C in the Owens Valley and Great Basin. The accuracy and update rate of Butterfly winds are outstanding and a tremendous asset it "convergence hunting. My only issue is its complexity, i.e., the large number of user-defined parameters available and what exactly their effects are on vario display, sensitivity and response. I have flown a Butterfly for 3 years, incrementally changing some parameters and am still not comfortable with its behaviors, especially when compared to the CAI 302.

It terms of "best" vario for X-C flying, the 302 is also very good and an incredible value.