http://www.jwfacts.com/index_files/similar.htm
The above link provides a very interesting comparison between the JWs, SDA, Christadelphians and Mormons.....it shows just how non-unique they really are.
My wife was surprised a few weeks ago when she found out the the JWs were not the only group that does not celebrate Christmas.......
Their shunning may be similar to the Amish, but I think the blood doctrine right now, at least the way most JWs think it is, sets them apart (I think most JWs have no idea about the matter of conscience concerning fractions).