While I have a LOT of issues with the seller (who has used at least half a dozen different IDs to avoid multiple Negatives AND claimed to be a victim of Hurricane Katrina when he had actually moved from LA to Arkansas MONTHS before the hurricane), the CD is something I'd be lost without. It's not perfect - the individual scans are huge and usually over 1MB each so it helps to have a basic photo management program like Irfanview. One of the catalogs is dated wrong ("1997 Legacy" is actually Fall 1993), and many of them don't show most of the Accessories pages so it can be frustrating trying to find things like wallets and smaller items.
The CD won't "make you an expert" but it will make it a lot easier to identify older items. One VERY important thing to remember and it's up to the individual buyer to decide, but selling Coach's photos and graphics is a violation of Coach's copyrights. The seller has had those listings removed before, so decide if you're ok with it. Just be absolutely sure that whoever buys it does NOT use the photos for selling purposes.