Some infos I have read :

1) Finale 25 and Note Performer 3 have latency problems.

2) MakeMusic says that these problems have been fixed in Finale 26, but some users have reservations (latency ok in note entry, but not in Playback ?)

3) Note Performer 3.1, in Beta, is supposed to be compatible with Finale (but which versions ?), and they are looking for Beta testers.

So, waiting for 3.1...

Thank you Michel! I have also read some latency problems both during insertion and playback, and certainly must be very annoying! It would be nice to have confirmation if with Finale 26 these problems were solved. The sample from what I heard on you tube seem much more natural and less mechanical than GPO5.

I find NotePerformer 3 much more helpful with Dorico than with Finale (I do not use Sibelius). In Dorico compensates somewhat for its absence of Human Playback, but in Finale I find I am much happier with the Garritan sounds and HP for any production work that requires an audio demo.

Needless to say, NP's latency issue makes it impossible to combine it with other sound files in Finale--or at least impossible considering the amount of time I am willing to spend to get them to work together.

That said, NotePerformer will likely improve; so for that and other reasons, I am not sorry I purchased it.

In the initial release of v26, we did fix the latency with NotePerformer as it pertains to note entry only. There is still the issue of latency during playback but this something that we are addressing. I am not aware of any playback timing issues when using a combination of NotePerformer and Garritan Instruments, these should sound together with the latency.

So with the next update , the problem should be solved?

I've started using NotePerformer and love it.  Input latency is fixed in Finale 26.  I haven't tried using it with any other plugins so can't speak to sync issues.  I'm also beta testing 3.1 which is a much more elegant integration with Finale than 3.0.  

The thing I most like about it is the balance of the orchestra is so good right out of the box.  And I don't have to fiddle with anything but the music.  So as long as the score is marked as it would be for real players the playback is quite good.