Looking to buy a 70-200 2.8 IS. The price seems to have gone up quite a bit recently, making me look to Ebay. A person has one on auction for buy it now price of $1599.95. Not a bad price, right? then he says it's in pristine condition...cool! The only thing is this...it has a date code of UR, which means it was manufactured in 2003!!! He bought it in 2004. Is he smoking crack, or am I?? Does this lens hold its value that well? Have the optics changed at all in the last 5-6 yrs? Please let me know your knowledge or opinions. thanks very much in advance, Gregg.