Never had that luxury. Been in business class on the odd occassion. It really is quite a bit better- especially the food.
People complain about the price of airfares but airfares are much, much cheaper nowadays than way back before the advent of the Jumpbo Jets, e.g. B747s DC10s and now, the giant Airbus A380. It used to cost about six months pay to take long, international journey in a Sandringham flying boat way back in the 1930s and 1940s.
Fellow I know, who is now in his ninety's, took a trtip from Johannesburg to London. They flew up the Nile Valley. Each night they'd stop over somewhere at a luxury hotel. Took about four days to make the trip. But it was luxury all the way. Now that is First Class!
What keeps the airfares low by comparison is the airlines can pack people in like sardines. Whilst we're prepared to put up with it, they'll continue to do it.