I bought a long haul seat for my first Rocket. It was just overall bigger. Russell builds their seats on the stock seat pan, but anyone who has seen a custom Russell seat knows that the seating area can be huge compared to the stock pan, and both pillion and rider can get more support.
FWIW, I can take the stock seat for a couple of hours without too much flinching.
I can take the long haul seat for maybe half a day. So it might be considered "better."
But if I want to ride the bike day after day, the Russell "Day Long" seat is the way to go.
I had one made for my first Rocket, and I have just moved it from Rocket to Rocket over the years.
Regarding Russell, what makes it best is that it is custom made for your leg/thigh/butt configuration, and the design takes into account how your arms will hit the grips. This last issue is a surprisingly important aspect of seat design.
So ... in my opinion, the long haul seat is worth a try, and if you're a lighter sort of guy (sub 200 pound class), then it may do the trick for you.
But if you're on the large size (200+ class), foam seats aren't likely to be comfortable for more than about half a day. The Russell suspension system has a definite edge.