i went through a similar phase of being on the fence with the H9000, assuming that i would not be fully satisfied unless VSIG came with the package.
after going around in circles for months reading and watching every demo video i could find, i finally decided to take the plunge. and after almost 6 months owning the box. i can easily say it is the single best audio hardware purchase i have made (excuding synthesizers)
from a usability and UX point of view, i think the H9000 has almost perfectly nailed it, and at no point now, after having initially set it up, do i think the user interface hinders me in any way or stands in the way of creativity. Obviously there is room for improvement, like anything. but i se nothing obvious that demands to be fixed.
the ability to edit things on the computer screen visually really makes the thing infinitely more flexible than the previous Harmonizer i used, the H7600.
from a UX point of view, its essentially more like 16x H9s
The ability to conveniently save FXChains as a file on my Mac file system, with a given audio project, is a convenience which means my effects are tied to my audio project in a way that is hard to mess up.
The sound quality itself, like so many others have said before, really is just way better than other effects units ive used. and the example i always use to demonstrate this to sceptics is to use a relatively simple thing, such as a basic delay. and just compare that delay to whatever else you might like using, there is a patch 9101 Digital Delay which is pretty basic . but just sounds really really good. again, you could read a billion pages of reviews and watch a lifetime of demo videos but until you get the box installed in your studio and hear it with your own ears, you wont really know.
the issue of it not having VSIG was more than compensated by the ability of being able to stack up patches, and my concern about being stuck or getting bored with the built in Algorihtms limits has not happened and now, in use, i dont think it ever would as the comination of the quality of the effects + the ability to stack up multiple algos means that, the potential combos are mathematically mind boggling.
the one thing i do wish the box had, which i imagine will be implemented in the future, is a more robust midi remote control ability so i can automate things programatically from a DAW or other midi device.. but beyond that. its 99% joy.