Reply to "sniping time?"

AS does have a very high rate of placing the bids. So far it's failed to bid for me once, and then it wasn't AS's fault, it was because e-bay's servers went down. So I've learned to trust AS to do a better job of it than what I can.
I can relate to Very Important Auctions. But whatever it is eventually does come up again, believe it or not. At one point (the auction mentioned above) I was worried because the item was a CD released only in Europe for a short time and it's out of print. (I'm in the USA.) It took 3-4 months, but the item did come up again. And AS sniped it for me. So even if you do miss out this time, things eventually do come up again. And a lot of the time, the second time around is at a better price! (That may not help your case of the jitters much, ) If you do both proxy bidding and sniping, you may well drive up the price because others who may be watching will see your interest and bid higher. Sniping keeps your cards hidden, so to speak, so that you can come in at the last minute and bid without driving up the price with a bidding war or letting proxy bidders know you're interested so they should bid higher.
My best advice would be to set the AS bid at the highest you are willing to pay and let it do the rest. There are no guarantees in life, but that should give you your best chance.