I hear what you're saying, Kevin, and I do have a bunch of 4x5 holders, but a couple of things:

1. I'm not sure yet whether I'll be doing any 4x5. I have a multi-format holder for 120 film, and five working 5x7 holders (plus a sixth that is pretty rough to get the slides in and out, but I might get it working). I got a very good deal on the 5x7 holders, but wouldn't call them inexpensive. My thought right now is to do 6x9/6x12 color transparencies and 5x7 B&W. (4x5 color film is really spendy, and doesn't exist in 5x7.) And I don't mean for just this trip, but maybe for always. I'm just not a fan of how square the 4x5 format is. That's just me, but it's why I got a 6x8 back for my RB67, and why I don't plan to keep my Pentax 6x7 much longer. I'll try to keep an open mind, though.

2. For this trip, I plan to bring along 50 sheets of 5x7 FP4+. I'd like to bring more, but want to deliberately limit myself, so I take more care and do other things. The trip will be about three weeks long. 25 film holders would be quite a load!

Still, I am glad that I got the five (maybe six) 5x7 holders. It will really help on shorter trips. I had only paid for four, to a seller on eBay who had 24 total for sale. She sent me two more at no extra charge, just because no one else was buying them! They're older, and not pristine, but except for the one in questionable shape, they seem to be in fine working condition.