I had the same crap experience helping out my buddies southern rock band back in the ‘90’s.
The keyboardist insisted on using it even though you could easily use a synth (or whatever those guys call it) version at that time. Modeler vs Tube wars foreshadowing!
As a guy who gigged with a real Hammond tone wheel organ in the early '70s...there are reasons for using the real thing, (and one big reason not to, namely the tonnage you've got to drag around!).
You're synthesizing three things, not just one: the tonewheel organ, with its inherent nonlinearities on EACH wheel; the amp; and finally, the spinning horns and rotating drum around the low frequency speaker to create the doppler effect. It's just not gonna happen.
Imagine playing a keyboard synth guitar and then plugging it into a modeled amp. Now throw in trying to model or synthesize doppler effects at different rotating speaker speeds.
It's too much of an ask.
This isn't modeler vs tube. I don't know
any keyboard players who'd claim that an algorithmic or modeled Hammond can do what the real tone wheel Hammond-plus Leslie speaker does. We're not talking about subtle differences as with modelers vs amps.
Part of it is the difficulty of duplicating the nonlinearities of a tonewheel organ, each one contributing its own set of them.
The other thing is that no IR, no algorithm, nothing has succeeded in duplicating the doppler effect of two spinning horns, with their very high efficiency and oomph (they don't need much power), and then there's the rotating low frequency drum operating at a different speed. as it goes around the bass speaker.
Even Eventide, who've done a creditable job trying since the '80s, haven't been able to manage it on any of their products.
That doesn't mean I'd be willing to drag a real Hammond around to gigs now - I wouldn't even if I had roadies - but I'd be awfully tempted to re-box a real Leslie speaker in a lighter, road-worthy cab.
"You speak as if you weren't already nearly dead, with all this 'road worthy cab' talk."
"I'm ignoring the 'nearly dead' part because (a) my Ouija Board hasn't told me the exact date, time or place of my impending doom, and (b) I'd like to have a good time while I'm here, K?"
"Your idea of a good time is imagining you're still gigging?"
"Got a better idea?"
"I'd say...no."