I did my tails and third brake light with VHT Niteshades as well and cleared over it properly. They are very glossy and smooth and I am very happy with them. My only concern is that I read somewhere that Niteshades can fade out over time. Mine have been done close to a year or so now and I haven't noticed any fading but I find myself looking at them all the time and thinking "Are those fading some? Do they look a little more red or is it just me?" Honestly, I think it's just my imagination so far. But if I ever do have an issue with the Niteshades I too will probably get a professional paint/clear job done with true automotive materials.
Here's a close-up of the Niteshades finish.
And a distance shot of how they all look. Truck has changed a little since then and it was dirty, lol.
As for the heads, as someone else said I would NEVER put Niteshades on my headlights. Never never never, lol. I actually like the chrome reflective look of my heads with my silver truck but if I wanted to tint them I would look at the vinyl film by Lamin-x or similar. It's cheap, relatively easy to install, and easy to remove if needed. I have Lamin-x optic blue on my fogs and love it. It really sets them off in person. I have had it on there six months or so with zero issues.