Mainly following along but I'll share a few things in the meantime.
I've been running my sk5000 without issue since August 2018... currently on my second large roll. Initially replaced that piece you are all talking about in 2018.
Here are some observations I've shared with our Minnesota club during that time.
To remove the used fleece you just put a large pcv pipe into the open end of the motor so as to avoid hitting the motor screw, I prefer a 1.25-1.5" pipe, then pull. Slightly easier if you lube the motor housing under the sleeve. I've never had the cardboard tube get wet though.
I've also tested several different brands of paper, including those I sourced on my own from different manufacturers, to test and find a cheaper option... which I did with a catch.
Keep in mind I run a 1" pipe on full siphon from a 5'6" drop which is more flow then many run through a sump these days. I also have a stocked 300gal tank with 4 feedings a day and coral feeding nightly for a waste reference. There are two other drains that bypass the unit and go directly to the sump.
Aquamaxx worked the best as an alternative, modification suggested to unit for smoother feeding through it, and you'd need a high flow as well as a higher volume of waste than me BECAUSE the paper on average spent ~2.5 days submerged (officially breaking down/releasing organics at that point) where the ClariSea brand was only 18hrs submerged. Anything longer than 2 days polishes water but doesn't prevent the breaking down of organics.
I went back to the ClariSea 5000 paper because avoiding waste breaking down was more valuable. A smaller, lower flow, or lighter stocked tank would have an even greater incentive to use the original paper.
Side observation is my skimmer is now greatly oversized and a giant glorified air stone due to the effectiveness of the paper. My snails also keep spawning but I don't get babies since running fleece. I've considered going without paper between rolls for a couple weeks at a time to boost other life or at least bypass the ClariSea for a day if I see spawning.