So, I had bought an EOS-1Ds to go with the old 70-200mm f/2.8L lens that a reader had graciously made me a fire-sale deal on. And due to KEH's error and their appreciation for my honesty, I wound up with an EOS-1Ds Mark II for $399. And I had an EF 40mm f/2.8 still laying around from the days when I was shooting Canons.
Because good things, like bad things, apparently travel in threes, I saw a new listing pop up on eBay for a Sigma 28-70mm f/2.8 EX DG lens...usually about $3-400 on the used market. This one was $167.
The seller had an excellent rating, offered a money-back guarantee, and said the only reason for the price was because of a crack in the plastic shell on the lens.
That seemed worth the risk for the price.
The lens works fine. It's an older Sigma EX zoom, so it's a little soft wide open at longer focal lengths and can hunt for focus in dim light, but for a $165 lens, it seems to be the berries. Now I have some wide(ish) angle glass to go with the 70-200 tele. Can't wait for vacation!