My family and I have been on the road and living in our truck camper for the past 10 months... the four of us use the toilet every single day and dumping the black tank has been catch as catch can, so sometimes every day and sometimes just once a week. While boondocking we do our best to conserve water which means that we use as little as possible for flushing. We have also been at campgrounds with full hook-ups and used a bowl-full of water with every flush. When we do dump, some of the dump stations have had water available for rinsing the black tank (my TC has a built-in tank flush system), and some haven't. That's a whole lot of variables.
I have purchased every imaginable kind of toilet paper; I started with super-soft two-ply stuff, but it caused complete clogs of the black water tank outlet on several occasions (not fun)... Then I switched to the one-ply RV stuff, which never caused a clog, but my wife and kids complained about its "functionality". Finally a few months ago I switched to Cottonelle brand "Clean Ripple". This stuff is inexpensive, available everywhere. It is single-ply, and septic safe, but it also feels thick and does its intended job very very well. No complaints from the family and no more clogs.
I'm sure that there are other brands that work well, but this is the one that I've decided to stick with from here on out

Cheers,
-Mark