Snowboarder,
Your snipe bid is the highest amount you are willing to pay. If the second highest bid was actually $150, your snipe would be placed at $300, but you would win the auction at $152.50 ($150 + $2.50 increment). But, as you may know, with ebay’s proxy bidding system, just because the current price is $150, does not mean that’s the current high bidder’s full bid.
Just remember, having AS place a snipe is no different than placing a manual bid, only it's a few seconds before the end of the auction.
Happy New Year