Jason as I can see from manual junods is only 2 zones controller
Also korg kross isn't 16 zones controller because midi notes can be sent on only one channel

The fact that keybord are 16parts doesn't mean that can drive 16 zones

There was a NAMM video where the presenter mentioned being able to use the 16-part mode to control external devices. Maybe he was wrong - since the MIDI implementation and manuals do not clearly show that the below link flexibility applies to external MIDI messages (perhaps just internal sounds).

https://www.youtube.com/watch?v=BDEPU6gxHz8

Note: above is not the NAMM video referenced.

Looking the video it confirm that juno is two zone max. 16 parts can be assigned to two zone but it can't send in 16 different chennels I think

FYI, I checked with both Korg's and Roland's tech support and quickly received the following from Roland:

Yes, the 16 parts in a Performance can transmit on different MIDI channels, so it is possible to control up to 16 channels from the Juno-DS88.

The feedback doesn't match your previous conclusion - which is fine. I'm not convinced there is a conclusion yet. Trust but verify.

Jason did you explain that you have to trasmit midi note on 16 midi channels at the SAME TIME?
Because if not the Roland answered could be right but not aligned with this request.
I think that only rd2000 can match montage driving....but it cost so much

I understand your question and issue with the ambiguity. I've asked for a clarification.

Response from Korg regarding the Kross:

In the Kross, you can assign 16 timbre / program splits in a combination where each program can have its own MIDI channel with the ability to control up to 16 external MIDI devices / instruments.

Please see page 77 in the Kross Parameter Guide for setting the individual MIDI channels for each timbre / program in a combination. This will provide the ability to control up to 16 external MIDI devices / instruments. I included a link below to the Kross Parameter Guide.
http://i.korg.com/uploads/Support/USA_KROSS_ParamG_E.pdf

Update from Roland:

Yes, if you have all 16 parts activated, the Juno-DS88 will also output on all 16 MIDI channels.

So it appears both the Roland Juno-DS88 and Korg Kross, according to tech support, offer external control of 16 zones as originally stated. Feel free to do your own testing, however, to confirm.

Jumping back to an alternative of using two 49-key controllers: I am not aware of any single synth or MIDI controller that allows for a single zone to be split across multiple ranges (non-contiguous note range). Using two keyboards you could target the same MIDI channel and have part of the range mapped on one keyboard and another part of the range mapped on the second keyboard.

It would be great if all MIDI controllers and synths allowed each key to map to a different MIDI channel (and for internal sounds, allow to map any key to a given element - in Montage speak). So we could have a list of keys rather than just a contiguous range. Currently in order to have non-contiguous ranges, I have to use multiple duplicate PARTs to realize this (with non-overlapping key ranges).

Another alternative:

You could get even a single-zone 88-note controller and use some device between the controller and Montage to map out your zones. Something like MIDI Solution's Event Processor ( http://www.midisolutions.com/EP_Guide.htm ) - there's also an Event Processor Plus. I'm sure these can handle routing options (re-channel MIDI) but they have a product more specific to do just this function ( http://www.midisolutions.com/prodrte.htm# ). During previous research, there's other hardware out there that can do complex MIDI intercepting and re-routing. I wasn't able to find the more involved one. It likely costs more than the midisolutions offerings.

Jason seems that you are right!
If some of the forjm have kross maybe can confirm this capability.
Thanks a lot

No problem. You may never want to get either keyboard for what you're doing - but at least I wanted to have the facts confirmed.

Using a small MIDI router or event processor (doesn't have to be MIDI Solution's) may be the best way to go. Since the device can solve lots of problems and remap just about anything you want to do (the event processor). For your purposes, the router is more for just creating zones for keyboards that do not have zones or have a limited count. It does not give you faders for the zones - so there are advantages and disadvantages to the approach. Depends on how much you want to spend, I guess.

So not to alienate Yamaha too much - but the Midi router + an 88 key Yamaha keyboard (without zones) would work out. Not going to have aftertouch - the P-45 would work in combination with a MIDI router. 11.3kg

I would want to have more sliders and knobs and buttons, though - and the P-45 doesn't have much in that department.

... and if you're willing to get the router to solve the zone issue - this brings in lots of other choices.

Studiologic Numa Compact 2 is 9kg. It does have aftertouch. pitch and mod are strange joysticks - maybe you can get accustomed. And it has internal sounds/effects - so probably going to make the cost higher due to this. Looks like street is 450Euro

Or Nektar Impact LX88+ with more knobs and faders. - no aftertouch. 8.2kg

Aftertouch does limit the less expensive options. I know you said it wasn't a requirement - but that seemed to be some "waffling".

Jason some colleagues in Italian forum wrote that kross work in 16 parts only with sequencer and arpeggiator but not from keybed...maybe they wrong but the only way is that someone who have kross test it

Page 71 (parameter manual) - They have to set Timbre status to EXT or EX2 or the external device will not be addressed using MIDI channels in the MIDI setup. The Kross owner's manual doesn't give any examples setting up external devices in a clear manner - so I can see how there could be confusion. The owner's manual only shows how to setup the arpeggiator case. After setting this Timbre status up, the page 77 (parameter manual) MIDI channel for each Timbre will setup the MIDI send and receive channel (zone/split).