I looked at an S when I was in the middle of looking for my E63, the pull of the badge was strong but the car wasn't worth the premium (to me).
If I *had* stretched to the E63-S price then frankly I could have then made the case to myself to get the 213 E63, as Will points out - I paid £28,000 for my S212 E63 and hope to get around 20K back for it in three years/24,000 miles. I'd have spent £37,000 on the S, and probably aimed for 25k in three years.