It may well be that most of the distortion models are the same, but just a ton of new ones have been added like the RC Booster, Mad Professor Blueberry, and B3K/B7K.
The Bass Big Muff on the old gen is much better than the NYC Muff on the B3n though. No BBM on the new one for some reason!
Honestly the B3k and B7k are what made me head-turn and take a look at the pedal again.
I'm starting to lean away from the pedal again though. I was playing around with my sub'n up and my Rumbles OD and was able to get some pretty fuzzy sounding tones, especially with the octaves going. I do really like my amps OD, which poses an issue with how I want to use the Zoom.
I essentially want to stick it before my Orbital Mod so I can use the Darkglass distortions into the mods. But the main use of the pedal would be delay and looper. So to get my delays sounding properly with the Rumble OD (same with the mod) I need them to go in the FX loop. Which in theory I could put the Zoom and Orbital mod in the FX loop but then we go back to the Darkglass pedals (my main reason at reconsidering the Zoom) and I'm just not sure about going E Filter>octave>comp>amp>modulation>Zoom (dirt>modulation>tremelo>delay>looper).
Plus the Zoom wants a lot of mAs. I'd have to replace my main power supply as it's only 1A or run two and power the B3n separately. And while either way I need a new pedalboard I have to double the cost to get one to fit the Zoom as none of the super cheap eBay boards are big enough.
But I lean back to the Zoom because it's cheaper then an EHX Canyon, TC Shaker, EHX BBM/SA MBD (if I do add dirt), and a TC Ditto (for looping with delay available). And unlike the MS60-B I can control patches and move around the pedal with my feet.
It's a tough dilemma, as they're all great pedals and even if I could test them all in store I'm never going to get enough time with em before I buy to really get to know them.