Well, 4 fuzzies would equal bigger than a hopper. I usually will double up on a size when they are between sizes. This stage usually only lasts about a month or so before I move on to the bigger prey size. I can honestly tell you from experience, if your snake can take down 4 fuzzies in one feeding, he will be able to take down a hopper with no problem.
How much does he weigh? and How often do you feed him?
I do see that you have been keeping snakes for awhile, so you would know your snake better than anyone else. So I wish you luck
If he sheds that rapidly again, I would take him into the vet to have him check out for any illnesses or parasites. That is not typical for a snake to shed that closely together unless there is some sort of under laying issue.