Hi Dicko,
I have had the Elite S for almost 2 years now, having previously owned an Elite Glide, Elite SL and Elite, so I've had experience with all of them.
For an overview of the differences with photos see a previous post on this forum :
www.surfski.info/forum/21-fenn/18152-fenn-elite-s.html
Anyway, to put it in a nutshell, the Elite S has its advantages over the Elite, especially in smaller conditions, but in my view the differences are not so marked to warrant upgrading from an Elite in a hurry.