I have spent quite some time, maybe around 20 hours this week playing with just materials and mostly it has been the quad shaders, which I used for the horns and also for the skin at first, but then i found another material for skin that I had created a while back when I used to be really into Zbrush 1.23b. I really recomend that a good excersise is to fill a new document with shapes of things you have sculpted in the past, and get the lighting to how you want it, then spend some time on materials, playing with all the settings and learn the patterns between them all and get an idea of how to get the materials you want, well, at least close to them. Once I get time, which will be in a few weeks time I will post something with examples of some materials, like a set I made with five variations on the size of scales that they create in order to produce nice looking snake skin, for a snake or a character, which did not suit the dinosaur, but at least by exploring the materials I have many that will not go to waist and also have had fun learning. Thanks for the comments, I really appreciate them. I have to go to sleep no as I went to bed about 7am last night and have to get into university earlly tomorrow, so can’t get addicted to Zbrush again tonight… but it will wait, he hee. 
You are doing a good work, the texture is really kool.
Very nice. I love the texture effect you created. The detail is cool.
S
Pilou
The tests have been put to use on an Allosaurus I am working on
http://www.zbrushcentral.com/zbc/showthread.php?t=26299&page=1&pp=15