Moog site says:
The Sub 37 Tribute’s new features include Duo Mode, which allows oscillator 1 and oscillator 2 to be played independantly, programmable arpeggiator/step sequencer, two modulation busses with assignable source and destination options, access to 256 presets, and a 37-note velocity sensitive keyboard with aftertouch.
As for this vs. the Analog Four/Analog Keys, everybody’s got his/her own tastes as far as features, sound etc. Some people go for the bigger feature set, confident he/she will be able to tweak the sound to exactly what is desired. Some people go straight for the sound, features be damned. Some people want a simpler UI instead of having to memorize button combos and dive into menus.
In an ideal world, the sound, UI and features are all there. But in the real world, they’re often not, and so each individual must decide on what is most important…