I purchased the tablet primarily for my work in retouching photos and creating web graphics. However, I have found myself using it as my primary GUI navigation (web browsing, drag & drop) device, as well. I find it extremely natural to hold the Graphire's stylus, although after prolonged use I do tend to periodically switch back to my Intellimouse to prevent cramping in my hand. This is more an ergonomics lesson -- you know, the "Take breaks every 15-30 minutes" one no one follows -- than a negative aspect of the Graphire. :) I would have bought the Graphire even if it had not come with the wireless mouse which, while I have no doubt is precise, I do not find as comfortable or useful as my Intellimouse (I love its browser "Back" button capability and the smoother wheel operation).
While I had never seriously used a graphics tablet before, I have been a PDA (Casio Cassiopeia E-115) user for almost 2 years so I am very familiar with stylus-based input. I enjoy the natural feel of the Graphire's stylus so much I have taken to using it instead of my PDA's stylus when I need to update info. on my PDA while it's docked at my desk.
I'd recommend "test driving" a graphics tablet before buying as you will either love it or hate it. I'm definitely in the "love it" category... but it doesn't replace my Intellimouse entirely.