The Cubs were in the midst of a six year run of Topps team specific factory sets in 2005. The special set contained the regular 733 base cards, but then Topps included five bonus cards specific to the Cubs.
For 2005 they had cards of five prospects. There is good news and bad news that goes along with that...
The bad news....they were the exact same five that were given first year cards in the Updates and Highlights set.
The good news...Topps changed the pictures, so the factory set cards are different than the Update cards.
The bad news....its six years later and only one of the five prospects has had any sort of a big-league career.
The even worse news....the big-league career is with the Brewers.
I'll show the cards side by side with their UH partners, the factory cards on the left, the Update cards on the right.
When Topps stopped making Cubs sets in 2010, I can't say that I really missed them.