It IS hard to choose just one, but here are my favorites:
WOZ - unbelievably beautiful images and colors
IJ - bright vibrant colors (when the dreaded fade hasn't happened)
Bally Playboy - captures the spirit of the magazine and its most popular era beautifully, and the girls are great to look at
And, of course...
Elvis - great use of colors and artwork by Jerry Vanderstelt. If you are an Elvis fan, you will realize that the attention to detail regarding his life and career are incredible.
Last, but not least...
LOTR - more great artwork by Jerry Vanderstelt. It is so good that it makes up for the heavily pixelated style of the Sterns of that era