A shower on a flight is pretty exhilarating and the 380 suite is excellent.
So you're saying that for the 380 it's worth it but not other aircraft?
The question is for what length of flight is the premium justified? I booked DW in F EWR-ATH simply because J wasn't available.
A JFK flight vs EWR flight is also worth a premium for me. But it boils down to the overall combination of availability and connections. All of those take precedence over an in-flight shower.
EWR-ATH flight was delayed due to a snow storm. The availability of many ATH-TLV flights definitely helped. Especially where I was able to book some on Priceline and get full refund if schedule didn't work.