Undeniably, flying First is the best way to deal with long-haul commercial travel if you can.
However, as with a lot of things in life, familiarity breeds contempt.
When I were a lad and starting out on my pax'ing "career" back in the mid-eighties, I recall the excitement of getting ready to go to the airport for a flight to the States. Maybe BA, or AA out of Heathrow and God knows, how many stops on the way. It was an adventure, full of new sights, sounds and experiences. As I climbed the slippery pole, the Middle East and Australia beckoned and I started managing to get a few Club flights. At that point I was ready, as our cousins would say, to give my right nut not to have to go back to Economy travel. Over the next ten years, Club or UC became the norm then, in the early noughties, First became my home. And do you know what? None of it was as exciting as those wondrous early days full of new experiences and people. When I look back at the photo's I took, the memories of flight deck visits, hotel cars picking you up at the airport as a matter of course and almost empty 747's crossing the pond (unsustainable I know) bring back some real feelings of nostalgia. I was also able to eat and drink whatever fast food was served in the airport stopovers without putting on an ounce in weight.
In the end, First, UC or whatever, became boring. I guess I just got older and tired
My son and grandson started counting some of the old ticket stubs I kept along the way a few months back. They stopped at seven hundred and so have I. I'm elsewhere in the world doing something very different now and haven't been on an aircraft for six months - I don't miss it but I'm happy to have done it.
To answer the original question, First class and to be fair, flying in general, gave me great memories - that's probably worth something.