I have played many Yamaha acoustic pianos, C3's etc, and not ONE of them sounded remotely as bright and brittle at medium and low velocities as does the arranger sampled pianos... Just because you can make a great piano doesn't mean you can SAMPLE a great piano...
To be honest, in a studio situation, I prefer Yamaha to most others for a REAL piano, but if using samples, sorry, but thanks and no thanks!
I disagree with trying to filter warmth into a bright sample. It is NOT the same as using a sample that is already warm... As I've said, it is easier to brighten a full piano sound, than to try and create natural warmth from a sample that doesn't have it. If all the lows are pulled out DURING the sampling process, there are none in the sample to emphasize with EQ. All you are doing is dulling down a bright sound. That is NOT the same as using a warm sound in the first place...
Be that as it may, though, I simply refer everyone to P.Creek. Make up your own minds. If you like that 'tack hammer' sound, go for it. But IMO, it doesn't sound like a REAL piano.

Great in a mix, BAD at solo piano. I need something great at BOTH...