not bad at all
Not too much to comment really as the range of ear shapes is huge. I think the lower part of the tragus looks a little far forward but that might be the references you're using.
if you want to take it to a more detailed level or if you (or anyone else) wants to learn about all the areas of the ear then I can recommend the following page which has lots of reference material and good tips
The guy who runs the site is a frequent contributor to the mudbox forums and knows his stuff