I'd doubt the wider market appeal of them, from from a competition perspective I can say this would be VERY attractive. Once certified, you'd probably get a few of us that would just load up on a hundred or so because whenever we find something this good, we buy a lifetime supply before it disappears.

I do think the delay flexibility would be worth it as an option, not as a forced standard. I think most over 18 would be able to figure it out. I just think most flyers really aren't going to pay much attention to the difference between a 4 and a 5 second delay. If their chute comes out and their rocket comes back, they're happy. Slightly before/after apogee is for the purists.