I had my retirement auction online and would do the same again.  Larger audience with fewer people actually onsite (1 viewing day, or by appointment & 2 pick up days in my case), less stress about weather and no trash to pick up after the sale.  My online auction was held in the evening (convenient for online bidding) and was finished in just 90 minutes after being open for bidding for ~14 days.  Everything sold well and I was 100% pleased with the process.