Some folks use ebay for the thrill of winning a bid. Some use it to find pencils used by actual screenwriters with certificates of authenticity. I use it to buy stuff cheap.
If you look at the lowest price vendors on pricewatch.com and then look up their ratings in resellerratings.com, the trend you’ll see is that the vendors with the lowest prices also have the lowest ratings. This is probably because this is the only way to attract new business when your first-time customers do not come back.
Similarly with ebay, if you check items with low bids relative to market rate, they may have negative reviews or no prior business to have a rating.
Given choice between buying from mail order vendor and ebay seller for an item of same price and condition, I go with ebay. The ebay seller likely provides better customer service than the mail order house. They also have incentive to do a good job to avoid negative ratings.
With bid sniping, you can set the price you want to pay. You just have to be patient waiting for the market demand to reduce relative to seller supply. This only works for items with ample supply.