Verdict is still ongoing for me. I just received my 16" with Max and 32 Core GPU and 1 TB (standard "high" configuration). I am coming from a 2019 16" MacBook Pro with 8 GB RADEON 5500 and 16 GB of DDR4. Full disclaimer, I normally have my system plugged in, and I do not use an external monitor.
I will admit that my expectations are fairly high, based on all the positive press and comments in this forum, and other sources. At this point, I am not at all impressed with speed. The only place I noticed any difference in performance coming from an i9 is in generally scrolling on desktop and Safari. This can be chalked up to the weak built-in GPU of the Core i9. In Safari nothing (other than scrolling) is any faster, which is what I expected as this *should* be a function of your connection rather than the performance of your system. I spent most of yesterday in a BlackBoard (kind of like Skype) session as I was working from home. No difference from my old Mac in this app.
I installed Parallels 17 (was using it on my old Mac) and was pleased to see how easy it was to get a Windows 11 ARM VM up and running. It only took about 25 minutes before I was at the Windows 11 desktop (including download and install and initial Windows config). Windows 11 on this system is fast! It boots up (from VM power off state) in less than 5 seconds, it seems to come up much faster than MacOS itself does. The one program I still use that requires me to use Parallels is Quicken 2013, which is a 32-bit x86 program, that runs just fine in the Windows 11 VM.
The other test case I have is Diablo 3 by Blizzard (game). This is a Mac application, but it has not been updated to a Universal Binary, and uses OpenGL vices Metal. I do not thank that Blizzard is ever going to update this game, which is too bad. However, it ran OK on the Intel Mac, but had some severe graphical artifacting due to the terrible OpenGL drivers provided by Apple. Under Rosetta 2, it actually seems to run with the same performance, and the graphical artifacts are gone! This was improved from my older Mac. I haven't spent much time with it yet, so my opinion may change.
Final test case (so far) is with Unreal Engine. Again this is an Intel application which needs Rosetta 2 to run, and is pretty hard on the GPU. I got it installed yesterday, but haven't yet got to testing it out yet.
I still have to get Adobe Creative Cloud on here, and am about to test out iMovie to edit my son's Christmas recital. I plan to post a thorough impression of the new Mac in a week or so.
Thanks!
Rich S.