I don't think it would be any different than any other handle - only slippery if the handle or your hands are soapy. I have a Murker HD with a red mallee burl handle, no 8ssues.
I'd add that they could be slippery depending on how they're coated. Polyacrylic, polyurethane, and cyanoacrylic can all be slick when wet if they're thick. If they are slippery - just buff the handle lightly with some scotchbrite. They won't be as shiny anymore, but they'll be much easier to grip. (Don't do this on metal handles. Only coated wooden handles)