The two biggest asked for items when it was only the cab1 was to add a screen and to get rid of the antenna.
Fast-forward to the Cab2 and the screen has been added and the antenna (external) removed.
With that, the one (and only one) advantage to the Cab1 is that I still have much greater range then either the DCS handheld or the Cab2.
However, as BigDog pointed out, the screen and functionally of the Cab2 make is so much nicer then the Cab1. Honestly, if you were having a hard time with the Cab2, then I would bet that you could not handle the Cab1.
In my opinion I find the shape even easier to hold with one hand and NOT accidently touch a button. The screen has all the information you might need.
Slider for horn/bell and slider for labor are used very much by me.
Lash-ups are extremely easy to configure on the Cab2.
Lastly, among many other features, I run with a club layout and at larger meets the Cab2/base has the ability to change channels. The Cab1 needs separate sale crystals.
Hope this helps.
Charlie