[Perfectlap]

well its kind of like the 911, if you're considering between an 86 or 87 go with the 87 because of the drastically revised tranny. Same goes with the Boxster. The changes were significant enough that the price difference between a 99 and 2000 can't justify going with the "unrevised" Boxster.
From a resale point of view not going with a 2000 could cost you money.

btw, you can go with a dealer to the Auctions in Manheim. Its open to the public but bidding is limited to actual dealers.