Please Recommend Audiophile Solo Piano Recordings

ZUIO, are you looking for CD, LP, or hi-rez/SACD?

Now that Herbie Hancock and Bill Evans got mentioned, let me add Keith Jarrett. Unusual and unique style, his "The Kohln Concert" (ECM 1064/65) was the recording of the month at Stereophile mag, and as any other ECM offering it is definitely "audiophile" quality!!! Obsessing with Audiophilia: Silverman at Stereophile label got mentioned, let me add Alan Gambel "Chopin and Liszt Piano Sonatas" on Mapleshade, CD 07382. I spent quite a few bucks on Mapleshade hardware after listening to their CDs! Unique sound, I daresay even better than Naim and Linn offerings.
My understanding is that you are trying to "voice" your rig. Thats how I do it also, on solo piano.
XRCDs beat SACDs in my room. Get "Emil Gilels - Beethoven: Sonaten" here:  http://store.acousticsounds.com/d/96344/Emil_Gilels-Beethoven_Sonaten-K2_HD_CD
or Richter here:
https://www.amazon.com/Beethoven-Appassionata-Funeral-March-Sonatas/dp/B00024I3C6
"Highest Standard of performance" is a bit too subjective: Richter playing makes me cry, Rubinstein or Horowitz kick me into a different realm. Check out "Steinway Legends" on Amazon and choose your poison! Downloadable at http://www.prestoclassical.co.uk but usually its cheaper to buy off Amazon and rip.