Those MAC 1700 radios are really just a digital faceplate spliced with the ubiquitous KX175 radio's guts. The KX175 was a great radio electronically, its achilles heel was always the mechanical tuning mechanism. So, they got rid of the main weakness of an otherwise great radio and gave it some extra features to boot.
In addition to the flip-flop, you can store up to 10 additional frequencies (that's what the "next up" button does) so that you can complete an entire flight with no knob-twisting at all. Pretty cool... And of course, since it's a KX175 behind the "face mask", it's a slide-out, slide-in replacement for the KX175.
If someone still has a KX175 in their plane, this is a good opportunity...