What are the current recommendations for softsynths to use with BIAB under 64-bit Windows? I still have an Edirol SD-90, but realize that I won't be able to use it with Windows 10. Moreover, modern processors are fast enough that there's no need for an outboard hardware synth module.

I used Bandstand once upon a time, but that has also been discontinued.

I also realize that there is much less need for a separate synth with RealTracks; nevertheless, RealTracks doesn't cover everything.

So what is the current recommendation?