I'm strongly against banned SotF. The primary argument is that it's not an auto-win card, which some folks have already pointed out, and is the primary danger with cards. You can argue that Bargain isn't an auto-win, but I'd stare at you and make you recant.
You're not going to be able to keep some folks from creating nearly tournament-worthy decks, or broken combos. Simply ask them not to, and remind them it's a casual format (although I understand that casual groups can get very internally competetive, and when one member of your group starts comboing, then the environment changes to stop him). The best method of keeping EDH fun is social and peer pressure. For the EDH-ethos, Infernal Genesis is a much better card than Vampiric Tutor.
For me, a resounding BOO! to the EDH combo player. Be more creative; be more interesting. Or the rest of us are going to get you!
