I just saw this post while browsing Hisstank. I don't know who the guy is, or what his affiliations are, or if he's already on here. I just think the thread and the samples are worth seeing, though the parts might be pricey. If you read thr whole thread (samples are posted throughout) the guy discloses that his father was a sculptor for several toy lines, and the has also done work on a few lines himself. It's worth a read, if nothing else.
http://www.hisstank.com/forum/g-i-joe-customs/16317-25th-joe-customs-mad-joe-customizers-new-customs-checkem-out.html