The popular opinion is that the analog model is more accurate. I'm not sure if that's true or just audio urban legend. I actually have both, so I guess if I wasn't so lazy I could pop in a disc of test tones & compare them, but I'd have to run buy a 9 volt battery first.
The analog is a little more user friendly, and I'd recommend (having used both) that if you don't have one right now, you might as well buy the analog one. It also happens to be $30 cheaper if I'm remembering right.