the tuning-reality in orchestras today is around 443-445Hz and still rising. overall sound and overtones are not only affected by the tuning, but by the instruments and the musical imagination of the musicians, which is a question of tradition and education and, of course, personal skill. modern intruments are designed for modern tuning, so i can't see any problem. if one is stupid enough to rape a cembalo build in 1739 into 440Hz for example, the result won't sound good, i'm sure. to be honest, as a saxophoneplayer, i don't care about the overall-tuning, because my sound is created in my head.
just my two cent's