@Capt'n
Slight correction: though this thing is similar in purpose to the mag-safe connectors, they say on the web-site that it doesn't actually use magnets. It's the rubber ring that holds things in place.

I've read some reviews, and I found one that did suggest no noticeable difference in sound quality when going through the replug. I suppose the only way that I'm going to find out if this could protect the n810 on the elliptical is to order one. I'm hopeful that it will, as it supposedly pulls off most easily with lateral force, which is what one would expect if the n810 is sitting on a ledge in video-viewing position when the headphones get yanked downwards by a flailing arm.