I went ahead and took the plunge and got the Korg Module. Running on an old iPad2.
Sounds pretty good, but only a tiny bit disappointing.
Disappointing only because it's not really a synth. It's just a soundfont player. So when switching patches, there's a slight delay while it loads the next set of samples.
I coulda lived with half as many Clavinets and maybe devoted that to something else.
Went ahead and got the Triton add-on pack. Again, while the sounds are pretty good, they're still just samples of the real thing. Some of the samples are great.
Oddly, some are more-or-less repeats of the Module sounds. I mean, with the good Module organ sounds - and they really are good - then why would I want a Triton version of an organ? So there's maybe a half-dozen or more "repeats". Not exactly the same, but pretty close to what's already there in the Module.
Didn't spring for Ivory because it'd be a bit overkill for my band.
Also went for a copy of iM1. Very cool. Doesn't work and play well with Module, but a lotta fun to play around with, at least.