I picked up the Jackson back in 2001 when it first came out for the relatively small amount of $75. I have the complete master gu set outside of the Babe Ruth jersey and the dual bat cards which are just too hard and expensive to get.
Wow, that was a nice pickup. I didn't even realize there were duals in this set until you mentioned it. Only two on ebay, an amazing Aaron/Ruth ($1K) and a Hack Wilson/Billy Herman ($500). Numbered to 25, you are right - no way someone could put that set together, probably even if money was no object.