I've been on a quest for years looking for that sound with....well, you name it.
I had a 122 and 145 leslie and a couple of hammonds years ago, so I'm familiar with the real deal. I know what you mean with regards to the NI B4 II leslie. The leslie sim itself is ok, but the overdrive is just wrong. VB3 is better for that overdriven sound. Haven't tried the xils labs sim.
My quest is finally over for an authentic ballsy overdriven Hammond sound. I caved in and picked up a Neo Ventilator a couple of months ago along with a mint used Hammond XK-1 for a super $$ I couldn't resist. The Ventilator nails the overdrive. Sounds even better with just a tad of the Hammond overdrive mixed in as well for a little extra hi freq bite. The XK-1 leslie sim on it's own is ok, but the overdrive is pretty hashy sounding and not something I'd want to use on it's own. It's a night and day difference when running it through the Ventilator. Sounds great. I'm finally happy.