Gotta say I'm not sure I'm READY for a K-5 without an AA filter after having read a bit more about it -- particularly the article linked to above that references how it's mostly not included ONLY on medium-format cameras and/or those with really BIG MP counts.
The K-5 is NEITHER
So is the Leica M8. As the author says, the Leica M8 does not have an AA filter. It is only 10.3MP and APS-H -- much lower MP count than the K5, with a format a bit bigger than the K5 (1.3x vs. 1.5x) but not nearly medium format. According to the author, he's never heard of anyone having trouble with moire on an M8.
I found this thread with a link to an M8 shot with moire, but according to the thread it was easy to fix:
Since the K5 is significantly higher MP, the shirt would have had to have a much finer pattern for moire to show up on a K5 for the same shot.
Brand loyalty is a character flaw.