I would have to agree. I have just spent some time comparing the Arturia Stage 73 and the AIR Velvet equivalent from their default settings and I can get them close. But I also have a Korg (ancient M3) and I agree the sampled sounds in the Korg, although much more of a pain in the ass to tweak, just sound great out of the box. It's has nothing to do with the real piano feel of the M3-88 keyboard, as I can use my KeyLab Mk2 controller when I midi assign it to the Korg, and the playability while different, still gives me a very e-piano like response (although there is much more dynamic range on the Korg keys themselves).
So yes, I've also hear "Ben Gear" on youtube extolling the virtues of Pianoteq as well. For now, I have more piano than I can play, so the Korg is still my goto for best e-piano sounds.
By the way, same goes for the Korg Wurly vs Arturia Wurly and AIR Velvet Wurly. Korg wins.