Also a runner. When you are saying headphones you are refering to earphones which always fall of for me aswell, actual headphones have never been an issue for me though. Loving my $25 cheap chinese bluetooth headphones. And no I don't need to have great sound quality when i run due to heavy breathing anyway.
I vastly prefer bluetooth for working out, but I am incredibly sceptic about the sound quality from that lightning adapter.
Yea, Sound quality likewise isn't an issue for me when running, but I do sweat much more than the average runner. The loop headphones really work well for me.
I use over-the-head earphones, which can be tightly placed under a hat. No issues of slipping out whatsoever. TBH, they sound tinny and low-quality but like you it's not an issue since the wind and body movement affect the sound anyway, and I know they'll be trashed rather quickly.
I vastly prefer bluetooth for working out, but I am incredibly sceptic about the sound quality from that lightning adapter.