I have use the U-40 Perma Glass on several rods, two that were finished in 1981, and all of them held up very well indeed. Some of them were finished with color presever and some without. The Perma Gloss produced a fine finish either way.
A few things to keep in mind with Perma Gloss: It begins to harden as soon as the bottle is opened because the polyurethane resin it is composed of begins to react with the nitrogen in the atmosphere. Therefore, figure on buying the 1 once size and unless you are going to finish several rods within a two week period, consider the Perma Gloss to be a one rod per bottle finish. It is also rather thin (something I really liked about it) and it takes around 5 or 6 coats to get a first rate, glassy finish. And it requires about 4 or 5 hours of drying time between coats; therefore, figure 3 or more days for the wraps to be finished and another couple of days before you use the rod to make sure it is completely cured.
I prefer to have my rods finished without color preserver simply because I like the translucency you get when the finish is applied directly on the thread. This gives the rod a classic and classy look much like the finish the bamboo masters have used on their guide wraps.
Another really good and durable single part finish is any of the various polyurethane spar varnishes.
U-40 Perma Gloss is very useful to fill in those little nicks, simply brush a coat on and turn the rod section for 3 or four hours. Then put the rod away for 2 or 3 days before you fish it.
My favorite way to deal with these is to use Flex Coat Lite finish. Instead of thinning it, heat it up before you measure it out and mix it. Then apply it as as Nate reccommended. The heating of the unmixed part A and part B makes it thin. This method works like a charm.