Based on the number of complaints I've seen here from people who set their lead to 5 seconds or less, then didn't understand why AS had to add 30 seconds to their auction to make sure the snipe made it on time, I don't think I'll be sniping anything less than 8-10 seconds from now on. If I've bid my true max, and somebody wants it SO VERY much worse than me, and they can beat my entire proxy in 8 seconds, let'em have it!
Again, it's the HIGHEST bid that wins, not the last, and even if they do have time to see (and react to) my snipe, who's to say the bid they see is my MAX?