Of course Boston.

If I were you and the extra 5000~6000 is an issue, I will wait a little longer to save the money. (Or buy a used, in very good condition, Boston?) Grand piano is [relatively] a big investment. Once bought, difficult to change, especially Kawai does not have exchange program. You don't want to spend next 10 years looking at it and thinking "I should have...".

Your daughter is very good ;-))