I have been spending the better part of 3 days trying on different tips on my Atrio M5s. Along with the included tips I tried the Comply P series standard and Olives. While the Olives are fantastic on my UM2s, they are just too short for the construction of the M5s. On another note, that is my only complaint about the M5s! I really like the SQ over my UM2s. Must be the bbbaaassssss. ;)
The best fit so far and isolation is the included large bi-flange. The P series are just a hair small and don't quite get a great seal. I wanted to try out some other flanges or other tips. Suggestions for an ear canal that is a bit larger than the medium size?