I think this is an ancillary specifically for economy class passengers—you pay a certain amount to reserve a 4-hour slot on a bunk or something. I have no idea, but my guess is economy + nap slot would still come in well under the cost of a business seat. Plus they can sell those same 6 berths what, 4 or 5 times over in the same 22-hour flight?

If I recall correctly they’re not certified for use during taxi takeoff and landing, I’d imagine due to orderly-evacuation kinds of requirements.

This is exactly what I was thinking of when I wrote it down ;)