Hmm, well speed ist crucial imho.
I have an Apollo X4 connected to my iMac.
From time to time I use a plugin instead of my FM3 or AXE FX 3
The first time i did use the plugin ( a Pete Thorn Suhr model) iit felt a bit strange.
Well, the sound was good but I felt that I had to "work to hard" when i play.
Then I found out, that the roundtrip latency was 9.2 ms. So I maxed the sample rate to 128 khz.
The roundtrip latency dropped to 1.2 ms (reduced buffers as well).
Now, it's totally different. The feeling is way better.Butt i can only run one plugin ;-)
So, I want an FM 3 with 192 kHz sample rate.