As a Kontrol S88 owner myself, maybe you can expand a bit on how that would be useful to you?

Montage M's hands-on controls and intelligent displays are simply in a different universe compared to the minimalistic approach of Kontrol, and they are the best possible experience controlling Montage sound. They are both large keyboards, so S88 can't be thought as a more portable option to go on the road either. So what would be the advantage of using S88 instead of Montage?

Either way, if you really need this, you can now finally create MIDI templates in MK3 to control various parameters in either Montage M or ESP/DAW.

I would personally much rather find a way to use Montage's absolutely amazing interface to control my Komplete synths 😎

In any case, here's to a more expedite universal MIDI 2.0 adoption 🍻  

I can't answer for the OP, but here's what my own take would be ...

Last generation I bought the Montage 8 and returned it because I couldn't see hauling it around each weekend.  I "settled" on the 7 which was significantly lighter although still heavy.  The NI S88 is half the weight of the M8X.  If you rely on the keyboard's physical controls then using the NI is a big loss vs the Montage but it sure is lighter.

It is indeed lighter (still heavy for a midi controller), but both size and construction wise it is not something I would move around.

I have the Montage M7 sitting on top of the S88 next to me here and just had to move both - the M7 despite its weight, is built like a tank. The S88 feels more like a decorative piece you carefully put in place and hope to not move often. Unfortunately the S88s key beds also have a bit of a history not holding up well even locked in studio environments, I have two because of that. Otherwise, great looking units with high quality finish, clearly designed as a studio centerpiece.

If, for example, the OP is in a church setting and uses mostly Kontakt instruments with some occasional E.S.P. sound, then I would probably also go for the S88, it just fits better. The Montage M will put a better light show during Christmas though...