I really don't see an advantage to toilet paper breaking up. We use for the most part Kirkland and in looking at the test, it flunks. I also dump with a Sewer Solution (1" sewer pipe) and have absolutely no problem dumping.
Even if your toilet paper doesn't break down, it will still easily flow through the 3" or 4" stinky slinky. It easily flows through my 1" hose. So buy whatever gives you the most comfort in use or is the cheapest.