I think the latest versions of Visual Studio have gotten a bit better regarding performance. I initially switched because of performance issues with a particular solution (which is now fixed). I still find it slower than Rider though.
Regarding the debugger, I do wonder if I'm misusing the Rider debugger, because I've seen lots of comments saying that it's way better than the VS one.
The issue I have with the watch window is that I want to have 2 watch windows side by side, so i can compare to separate variables side by side. For Rider I find i have to use the locals window as one of my watches which is often really cumbersome.
Honestly, what I really want is an IDE tool to give me some sort of "diff" of objects while debugging, but the 2 separate watch windows is the best I've found.
I'm on the latest version of the preview (17.7). I think most of the performance enhancements were in the past 6 months, or even less. If you do a search for "visual studio 17.x performance" for x =4 to 6, you should get some devblogs posts about various performance improvements (some drastic).
My guess is that the VS team is prioritizing performance where they were previously putting out fires due to the switch to 64 bit.
I'm on triple monitors and I agree with the lacking multi monitor support.
Is Rider that great?
I'm partly just posting this to get some more content going here......