The reason I went to LeTonk was for ease of application under outdoor conditions without having to deal with adding solvents and the like. I honestly do not know how well it will weather. I do know that with my minimal experience applying varnish, Captains was somewhat difficult for me to use and get right... between brush strokes and strange crazing, I wasn't getting the results I wanted, and it was taking me a long time to get coats down. I wasn't satisfied.
I went to LeTonk and was able to double the area covered in the same amount of time; I found it quite easy to use, brush strokes all but disappeared, and I have no crazing. The results may not be the perfect glass clear deep varnish finish that I have observed on the rare "perfect" boat around here, but I still get a darn nice looking finish, that feels very good to my hand. And I get to spend more time sailing. GRIN
Time will tell as far as the end results. I don't varnish every day... and frankly I don't want to. I do admire your work, and the beautiful finishes I have seen on the occasional "perfect" boat.
I can also say that the results I have on my boat are turning heads on my dock... it works for me. GRIN