i havent done the bed but i will eventually, probably sooner than not if you know what im saying.
i have used a couple bedliners on different projects and love it
it is a pain in the ass mixing and using it before it hardens but well worth it.
i prefer the epoxy over the urethanes and i have tried one that was a blend of epoxy / urethane found them all a bit of a pain in the ass but they are far superior to any paint or undercoating i have ever seen or used
clean the surface very good with solvent and make sure it very dry the surface needs to be roughed up for a good bond
plan your job out and mask the hell out of everything but what you want coated
it ends up on everything like it or not.
wear latex gloves it takes atleast a week to wear off your hands.
do quick thin coats rather than try to get it thick and take to long worrying about it.
use one that you can get locally but dont cheap out on it the good stuff is expensive, figure atleast $200
the epoxy is usually pre tinted , the urethanes can be tinted to match the truck if you wish and i think there are a few epoxy's that are tintable now.