Looks like an old discussion has been revived -- but if I got the OP right, he said his montage has 11 layers. Last time I checked a couple of samples on the Nord, I seem to remember the number of velocity layers were in the same ballpark, i.e. somewhere like 9-11 samples for each key, or so. I think it depends on the particular sample and key, and I'm of course not sure if these numbers are representative of all pianos and keys.
So I doubt the Montage will sound much different than the Nord due to the number of velocity layers... just saying
As for the Roland RD Supernatural pianos, I agree that they have many more layers, but having played one for quite some years (my main portable "acoustic" instrument for ~7 years), I am MUCH more happy with the Nord pianos and the variety and "vibe" they have. I personally got really tired of the Roland sounds -- but that is more of a personal preference, and I'm sure someone else disagrees. But I must confess I doubt it's the number of velocity layers that makes the (liked or not) difference. I think there is more of a difference if you play a Nord S or M sample, with more stretched samples across keys, compared to the Roland, since a closely voiced chord may be somehow "in sync" between two adjacent keys, making it a bit harder to hear the voicing. But that is not an issue for XL samples on the Nord, and comparing Nord XL to Roland Supernatural is probably more of a preference in what you like to hear.