I know everyone loves the 89 Upper Deck Griffey RC, but this Donruss is my favorite.
I also think it is undervalued. Here's why...

Pop Report:
Upper Deck Card = 4,200 PSA 10's | Latest Price: $5,000+
Donruss Card = 2,100 PSA 10's | Latest Price: $750+

Let me know your thoughts.