The responsiveness is really dependent from the velocity curve, and I am lucky because the VPC1 has a velocity curve for both Pianoteq and Ivory, so I feel my American Concert D to be very subtile and responsive. The only requirement is to have 54Gb on a SSD as it works directly from the SSD and doesn’t need much RAM or CPU. If you don’t own an SSD, forget it.
You make and store your own velocity curves in Pianoteq. The same with American D.
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And even in keyboard controller and perhaps even in GP in the future who knows. But, it is much easier for me when the velocity curve is ready out of the box and corresponds to the real thing. But of course with all these velocity curve you can make a Steinway D VST even more responsive than the real thing 
I’m using Addictive Keys for all shows
I use Addictive Keys quite a bit too. Very light on CPU
I used Addictive Keys live for quite a while but have switched to NI The Grandeur which is almost perfect for my preferred sound and dynamics. Just have to be careful on the built in reverb and it can be a bit “smiley face EQ” on larger systems but both of those issues are easily adjusted if the situation calls for it. I like Pianoteq for some applications but it doesn’t suit me as a general solution and it’s definitely heavier on CPU.
Native Instruments NOIRE is my favorite lately. Forget about “Felt” and “Particles”. Just the pure sound, “wide open” Preset. I thought Pianoteq sounded too artificial. But maybe I was on a older version when I tested…