Probably a bit of a subjective question. UC has a lower shrink temp and in my opinion is a bit more forgiving. Check out this post in my Hog Bipe build thread for an example of wing tips and Ultracoat [link=http://www.rcuniverse.com/forum/fb.asp?m=8342343]here.[/link]

Monokote is a good product and you're entering the classic Ford vs. Chevy debate. If you've already started, there's no reason not to continue with MK. Take your time, follow the tips shared on the TF video and other threads here on RCU. If you've not done the tips yet, I suggest watching MinnFlyers video on covering Tips and using those techniques outlined there. If I remember correctly, he used Ultracoat.

Best of luck!

-MA