I was thinking how much that is! Each holder has two sheets of film, is that right? So Dave can carry 10 shots.
That's it! Two years ago I went wandering -- and I only had two film holders* for four shots -- figuring I would stop at the house and develop the results, then go to another site in the opposite direction. I actually ran paper negatives in the 8x10 and brought the 4x5 pinhole with a handful of holders loaded with film. By the time I got back to the house, the weather was turning a bit sour, and when I saw all four 8x10 shots had images, I said "OK, that's it!"
And yes, last year I was pressed for time so I took two each, bracketed exposures, of five variations in perspective of an old RR bridge using X-ray film and was actually fairly pleased with the result. So based on ten exposures I'm inclined to say "that's enough" and try to emphasize quality versus quantity. Last year I did another round of tries in late July and early August that were also encouraging. I won't claim expert status, but gained a little confidence. One of my WPPD shots and one of the August effort are currently part of a show on the "Schuylkill River and its Canals" at a history museum in Reading -- that still boggles what's left of my mind!
Although I admit, 8x10 pinhole shots contact printed won't compete with a 6-element lens, they are pretty doggone amazing for not using a lens at all.
I should probably try again with at least a couple of paper negatives this year. That's a process that still hasn't quite clicked for me, yet seeing some of the stuff Joe VanCleave posts, there's obviously a way to do it!
* The cost of 8x10 filmholders does not encourage acquiring a trunk full!!!