I only ever used a sniper once (I was in Spain, my internet was flakey at the best of times & a storm was coming in which guaranteed to knock it out... and I
really wanted a Lister 6/1 engine!) - about a week later my account was hacked & a bunch of DVD box sets I didn't own was allegedly being sold....
I've never used one since; I now rely on manual sniping - putting my max bid in with between 3-5 seconds to go. This has the advantage that I don't have time to panic & up my bid if I underbid... so I do have to go for my max price the first time. I rarely lose though! And those I do lose, were too rich for my tastes anyway

I've won auctions by 7p before now but the underbidder will never know that!
Actually Phil - you CAN tell if you've lost by less than the bid increment... because the final price is less than the bid increment! e.g. if I bid £50.25 and the item finished for £50.30; then I know the high bidder bid just 5p more than I did (and also bid before I did; eBay wouldn't let them bid that small an amount if my bid was already in)...