Jeff Evans
You might want to check this out:
https://www.youtube.com/watch?v=5zhXijvtkNc&t=14s
Core usage has been improved. Big time. It is more how you do it. It spreads the load over tracks and buses rather than a ton of plugins on one track. (Which if you are smart you don't have to do) I use a lot of virtual instruments all the time and don't have any problems doing so.
Quantum has got blistering latency now as well. That computer will set you back about $4000 though!
For those who get WOW effect from such videos...
The latency shown is really good. That means that audio interface, its drivers and the hardware of the computer was done correctly. That also means S1 deal with audio driver correctly. But note that the output is still 2 channels in all shown cases.
Is 800 tracks with 800 FXes really WOW? It heavily depends from what is going on with tracks and which FXes are used. Just for test, I have started Reaper in Wine under Linux on my notebook... 400 tracks with 1 FX each, so 400 FX in total. Plays fine
Tracks was simple duplicating of one track, with one clip and Cakewalk Channel tools as the FX. That obviously does not mean my thin notebook is extreme powerful computer and the best performance you can get from a DAW is running it under Windows emulator...
Since the speed of playing (the number of notes and waves per second) is the same for any buffer size, the disk speed should and stay constant.