MtnHtr,
Just speculating but I can't see where they would be any more susceptible to moisture than any of the other triggers would be. The lack of the connector bar would certainly preclude any moisture getting trapped in that spot. As you know, any trigger that resides in a housing is always going to carry some risk of something getting trapped in there no matter who makes it.
oulufinn,
This company carries the retaining clips. The safety lever takes a #5115 and the trigger pin takes a # 5560. The tool for installing the trigger pin clip is like a small nut driver that fits over the head of the pin and allows you to tap the clip down into place.
http://www.truarc.com/products.php
