My preference is the glossiest gloss I can get.  Or glossier.  I want to look down my my kayak and see the clouds.

Kim

With gloss varnish, multiple coats will produce a nice shine.

It's really a matter of preference.  I happen to prefer a matte finish and used satin on my Shearwater. 

I agree with LMF. Its harder so see imperfections through all the reflections.

The flattening additives in the satin finish tend to make for a softer coating. If you want a satin finish use it as the final coat. Build up with gloss first. 

I have to give a big thumbs up to the Systems 3 Spar Urethane Varnish-Satin.  I first laid down 3-4 coats of Petitts Hi-Build varnish (gloss), and then put down 2 coats of the Sys 3 satin.  The System 3 product was much easier to apply ( and thats good because I'm not the best with this sticky fast drying stuff on complex surfaces like the inside of my Wherry), and it seemed much less toxic.  The working time was much longer.   Also

-you don't need to sand betwen coats if you recoat in the 12-24hr timeframe

-my many imperfections are now much less visible (I mean the boats imperfections)

-the suns reflective glare is no longer blinding

While this look may not be for everyone, I'm really pleased with this product. 

And Hurray!- this is my final coat for this 1st year, and after it cures for about 3 days, I'm taking this baby out!

Hickory

Looks great!