Thanks for the input!

This is for loaded touring, btw. I think I will switch to the TravelContacts due to the frequency of flats in the rear tire.

I've been unable to find and debris or abnormalities on the rim or the inside of the tire. I also did not notice a pattern that would suggest a pinch flat. On some of the flats, the leak was slow enough that I could not find the hole, so I could not do a repair. I suspect the flats were caused by debris working through existing homes in the tire from prior flats.