I've had excellent results with a product called Trondack Dura Gloss LS Supreme. A single coat does the trick and it's thin. Like the others have stated the preparation is still important and many a rod has been built with flex coat. I'm no expert but a got many tips from one. Here's one that's pretty well known and I don't feel like he's going to track me down for sharing it.
Warm up the two parts of the mix - mix them by slowly stiring them in a cup first in one direction for 2 minutes then in the other for 2 minutes- I hold the small plastic cup over a light bulb while mixing. Try not to whip the mix, that would introduce more air bubbles. Once you are satisfied with the mix put it onto a double layer of tin foil - spread it out and put it over the light again to help get the air bubbles out. For some reason it seems to have a shorter cure time if left in the mixing cup. The heat will accelerate the cure so only use it for mixing and to pop the bubbles. I use the syringes to measure the 2 parts as they have a different consistency at the same temperature - it's important to get the mix correct.