I'll second John's recommendation on waxing the dark slides, although I just run the edges through a slab of beeswax and the buff them with an old t-shirt. I have nothing against Pledge...the beeswax just happened to be handy the first time I tried this, and it worked so well that I've never tried anything else. I re-wax the dark slides about once every three to four months and have had no problems with binding.
Like others here, I find the old black wooden Graflex holders to be a personal favorite. They're generally inexpensive, light, and I've not had one yet that needed a serious repair when I received it...I think I have ten of them. Just some re-taping and a thorough cleaning, and they've been good to go. I have some ancient Kodak holders (unpainted), but they're more difficult to repair and the failure rate is much higher than with the black Graflex holders.