Conti SC3 (235/40/18 95Y) - difference to SC2??

[Simon S4]

I am considering getting 4 new tyres on my S4 - and probably going for the Conti's - does anyone know the difference is between the SC3 and the SC2? I assume the SC3 is the 'next generation' hence better...? Not sure - the SC3 is slightly cheaper...?!? confused - any advice?