I find that sometimes I'll see two sellers auctioning the same item at differnt prices. One will have a buy it now for say 149 and another will have the same item for 130 but usually ends up selling for 165.
With me, I'm one of those people who will sometimes pay a little bit more. Usually if the guy selling the item at 149 only has a tiny bit of feedback or has to many negitives for my tastes. I'm more likely to spend a few bucks more for pieace of mind. Knowning that there is a far lesser chance something going wrong.
But if both sellers have similar feedback, you have to just be plain nuts to go with the higher price. I can understand if it's a trust issue. I myself, will shop around for days sometimes weeks, all over the internet, finding the lowest prices for items. Checking with websites like Epinions.com and ResellerRatings.com and others like them, making sure a store is credible. It's just smart shopping. I never go for the absolute cheapest though, more times then not, if the deal is to good to be true, well you know that saying.