Personally, I bid what I'm willing to pay as early as possible. A last-minute only wins if they pay more than what I thought it was worth.

When I sell, it's too annoying to get all the bids in the last few seconds, so I often offer discounted or free shipping if the winning bid is placed more than 24 hours before auction end. That way, I bone the "snipers," which makes me happy, because such last minute bidders dishonor real snipers.