I prefer the 9600 over the 9400. I had a 9400 but traded it to a friend.

9400 felt to top-heavy meaning if held it in hand, felt like would fall forward. 9400 also does not play sounds, only beeps.

But it does have the metal scroll wheel.

If I had my pick based on form factor, it would be a 9300. However, 9300 does not do ProntoScript. But I love the form factor. If you want no scripting, check ebay as I saw 2 up the other day and almost bought them.