I've not made this comparsion, but I own both N38IIs (comparable to an E60, I think) and S38IIs. There are certainly differences, and overall I think the S38 is a more refined speaker, but the N38s are great as well.
I think the E90s and E100s will be outstanding for HT or a music rig. The S312s are monster speakers from the Studio line, and, again, may be more refined than the E series.