I have the Treo 90 along with my collection of Palm m100, IIIc, Vx and something else. As I do some Palm programming, you have to try out such to see if it's something you'll like.
Remember that there are some that abhor grafiti, so no design makes everyone happy.
Bob
I must have missed this in reading about the Tungsten C features--can input be made on this model with a stylus (graffiti) or is it limited to input via only the keyboard? For a user who would want to more often use the graffiti feature is the Tungsten C a better model or would the Zire 72 be best?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic