There was a major redesign in 2005, and the 1999 to 2004 Grand Cherokee models are essentially the same, as are the 2005 and up -- so I would break it down by year, ie. 2003-2004 and 2005-2007.
Also see my comments on the '99 - '04 models here and other info in the Grand Cherokee forum.
http://www.automotiveforums.com/vbul...d.php?t=880045
As for likes and dislikes, I'm very happy with my '01, wouldn't change a thing.