I have the widescreen intuos 3 since at the time, intuos 4 was coming out, and the 3 series were a lot cheaper. It really depends on your budget, whether u like drawing directly to screen, or prefer not having your hand in the way (tablet). Personally, I like not having my hand on the screen itself and I have fairly good hand-eye coordination, so I prefer the tablet. I also have a tablet pc (laptop where u can draw on the screen) but I'm having trouble getting used to it, so I have a feeling a cintiq and I wouldn't get along as well.
My budget is ~1300aud. I am fine drawing offscreen, although drawing to a screen could have possabilities... another thing is the cintiq is the same technology as the intuos3 so I belive with the calibration settings it should be more capable drawing wise and calibration wise than a tablet pc. I dunno, what size is your intuos? do you like larger or smaller size tablets and do you think an XL would benefit over a large or detract in theory? (it is alot of money to shell out on one thing)
I have the Widescreen intuos 3, 6x12 or something like that. I like medium sized tablets. I prefer drawing small, but not too small. I got the widescreen to match my widescreen monitor, so it works nicely.