I use Captain's Z-Spar on Wu-Wei's brightwork. I used slmost every type of
varnish before, and it looked like crap after a few months. I tried oiling the brightwork, but you have to keep on that. The Z-Spar was my last resort. It took a year and a half of Florida direct sun and salt until it was time to redo the whole process. More expensive, it is worth the $$$. All I had to do was sand, stain (I used Min-wax from Lowes), and apply a few coats. (Apply thinly- this stuff is like syrup.) I am completely sold, and even used it for teak bilge covers (which it has handled a ton of abuse better than any other poly.)
Chris
US 30' Wu-Wei
http://www.diysailor.com