Tell Me about the Deckel Dialog 3 cnc control

Hi All,

Looking at euro mills, trying to decide which way to go.

How does the dialog 3 CNC control compare to the dialog 4, and can the 3
be upgraded to a 4? Is it easy to up grade and is it worth it?

What are the good and bad features of the 3 VS the 4?

Best Regards,

Paul