Cindy,
If I remember correctly my experiences with Damar probably had as much to do with my inexperience in application as with the product itself. I found that it would puddle up in places and was too shinny for my taste. The whole subject of varnish is a frightening one to me.
Because I like the finished look, and because I am so reluctant to change what seems to be working, I am now using a mixture of liquitex soluvar matte and glossy finish.
The mixture (tragedy), which includes cinnamon, sugar, turpentine, along with a cameo from Linda Brandon appearing as Ophelia (or was it Desdemona), can be found in the following thread:
http://forum.portraitartist.com/showthread.php?t=2895
Others have stronger views on the subject. I am no chemist, I don't enjoy diddling with these matters. I tend to park on something that works and turn off key.