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I would suggest Kellner or Valloti if you tend to play romantic period music, although those are a hair harder to tune than the easy ones like Werckmeister. Pianos can definitely take temperaments as long as you keep the A at 440 (to equalize tension on the harp).

Personally, I think Beethoven and Chopin sound great in Kellner, and I had my piano in Kellner for a very long time.

Definitely do it at least once.