From my dueling experience,85% ES with 20 hard points in telekinesis,and a fair split between life and mana(my sorc is currently lvl 86 and has 2k life and 3k mana after bo)works really well against most everything,Believe it or not she tanks about 6-7+ hammers in duel games.And she does on a regular basis.Most hammerdins die in like 2 direct hits from my 1600 orb,so its basically a matter of dueling skill,or how much cold sorb they're wearing.
As far as SvS goes,Ive owned most lightning sorcs,and been owned by most fcr fireball sorcs(big surprise there,lol).