The crud ring is worse on a barrel that has something for the ring to form on / hold on to in my experience with 777. I run an annual hunt event with multiple muzzleloaders - the participants all shoot a few shots for zero and familiarity, and then we load for a hunt. I have to balance what I can do in reloading the rifle vs what a novice or weaker person can do. The amount of crud ring plays a factor in whether I clean the rifle and then let the shooter load for the hunt, or if I can still reasonably expect that the shooter can reload again if they need to.
If you are doing bench work, it can be a PITA when sighting in, and if you don't want to stop and clean between groups, and if you are limited on time or range opportunity.
I have used the 777 pellets for years now, and weeded out most of my muzzleloaders down to rifles that don't build it up as bad, or don't really get one at all.
Had a new Knight trade this year that will be going down the road, as the bore is just rough enough to make loading very hard for more than 1-2 shots in a string. The bore "looks" pretty clean, but when you get into it - the roughness is there. By load three - you're forcing the bullet down to the charge, and it's an effort.