The latency, at least on my machine here and on VSTs , is for the most part, as good as real instruments with the odd, between once a day or week, exception which is expected on anything post Atari and even that had it’s mysteries.
Now I can’t tell exactly how the problem affects you but in my experience most midi timig problems that look like this (most, not all) are to do with stacking things like snare drums. (drums’ll do for now as an extreme example, other things can wait a bit)
Now in the real world stacking snare drums can have it’s problems but with the effects of midi it’s compounded by most of the midi limitations with the exception of a couple of instruments. These can make the problem seem much worse than it really is. Things like strings are, or should be, a lot more forgiving than drums due to their being more ephemeral as a medium so in my case I’d allow quite a lot of movement on these.
I’m trying to get a more focussed handle on what’s happening here as well as consolidating my thinking so please bear with me. I’m trying to ascertain whether the problem is musically related or are we dealing with machine music accuracy here at least in part. To the former a little drift won’t matter but the latter could be a big deal.