I haven't tried the stock tips, but I agree.. They would be fine without the raised section on the back side. I'm back and forth between 2 flange M9 and M11 tips that I got from suggestions in this thread.. The stiffer M11 tips seem to work better for me, the M9 Balanced are so soft that after a few minutes I feel them move and it loses seal.
I did find that as some folks have suggested, wearing them over the ear, has helped, and they stay in great that way.. Just not used to it at all, my last headphones were J wires and were light and never fell out..
But overall, I'm loving the warmth of the sound.. I went back and forth between these and my previous Sennheiser CX300's and the CX300's have a really hollow sound compared. I think these will end my quest to find good IEM's, assuming I continue to adjust to their wear and comfort.