I have bee testing round trip latency with VST plugin and the results are just amazing.
Using a mic in input one, routing to PC, VST host Kushview Element, applying Fabfilter Pro-Q3 (equaliser) and Pro-R (reverb), sending back the signal to the PC on input 2 set to digital,
I ended up with 6 ms latency.
If you add system latency given by the ASIO driver ( 1.67 in + 3.50 out) at 16 samples 96 Khz, I calculate 11 ms only.
This is very good for USB audio interface and having tested all with headphone there is indeed no annoying audible latency.
My PC is a mid range one, i5 12400k, moderne but the the most powerful processor.
Not having to scarify a channel to use external VST plugin would be a huge update IMHO.
Tks for reading.