The catalogue was an invaluable asset 25 years ago but in this day and age you'll get a much more accurate view of the market by looking at auction results from TCNC, Geoffrey Bell, HA, eBay, etc. It's still great for looking up factual information like serial number ranges, issue dates, etc. I really wish they would publish a high quality catalogue less frequently for those of us who aren't looking up to date info on the latest series.