I got the MTi2 recently. I was on a 2017 mac Mini when I got it. It worked great from a touch perspective but whenever running the Raven software, after about 20 minutes I would get a ton of white noise and static when tracking. I had a great opportunity to upgrade to a Mac Pro (black trash can) for literally peanuts so I hopped on it. No more issues.
I love the MTi2, but I am still having a hard time remembering I don't NEED my mouse anymore.
I use it on a dual monitor setup and it is a breeze. I did have Slate Support help me set it up when they were trying to troubleshoot the static/noise issue. Now when I hit my Arragne button on the Raven the tracks pop up on my main monitor and when I hit Mix, they go to the secondary monitor and the mixer comes up on the main.
Unfortunately i can not speak to the 5.1 question.
Here's my setup: