From what I gather, any plastic will get fairly slick when it get's wet, although the "Volcano" grip of the Spyderco's would appear to have the best chance of still being somewhat secure.
G10 with the proper texture, a la most Spydercos, seems to stay pretty grippy when it get's wet. Heck, the G10 of my BF Native stays grippy even with light oils on the scales, like Rem oil, etc.
The black teflon coating on the Benchmades is supposed to protect again salt-water corrosion, and is supposed to maintain a decent level of protection even when it starts to wear off somewhat. It is supposed to penetrate the surface level of the steel a little.
I am really leaning toward a Boye Basic to take with me if/when I go to Maui next March. It looks like, for me, an ideal set-up, except for the fact I'd have to make, or have made, a concealex/kydex sheath for it, so I could clip it.
I took another look around for the Boye folders. Those are really nice.
Oh, and for lock resistance to crud... I think that the liner lock set-up, when it is done correctly, is the most resistant to crud, based on a quick test that someone did not too long ago. I don't remember the name of the thread, unfortunately, but I think it was less than 3 months ago. The test include, IIRC, a lockback and the rolling lock as well. I think the rolling lock was the most susceptible to fouling by crud, with the lockback in the middle.
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It just a ****ing staple!!
Guess who...
St. Mary's County, Republik of Marilundt