It has been just over a month. While not using my Arm machine full time, there is nothing I cannot install and use on it, that I am using on a Wintel machine. I found one quirk, in my own software, which I was able to fix via a slight coding change, and/or via changing the emulator settings to the safer option.
As for comparing program speed, once an x86 based app opens, it is tough to see any perceptible difference, at least in what I do (productivity apps, my own apps, program coding, etc.) Load time is probably +20% (relatively insignificant) as the emulator "does its thing". I am comparing apples to apples, a new ARM based machine and a new Intel machine, both t=with the consumer level chips (not the pro level). Of note, the apps I use most often are x86 apps, not x64. Might make a difference, might not.
I suspect the emulator on Macs (usually Parallels) is likely as good, maybe even better than WoA/Prism because of longevity. For certain, I have customers using Mac/Parallels, and a few using WoA/Prism. My own payroll and accounting is now done using my WoA machine.
For me, the different is power use and heat. WoA is less on both fronts. There is talk that Intel has a new chip in the works which will compete on both fronts, but only time will tell. The better news is the silicon is becoming more and more immaterial, since the emulators are getting better, and chip speed makes the emulator overhead barely perceptible for all but gaming.
For a recent 5 day trip, I used my WoA machine, to access my Wintel machine (left at home). I did not have to charge the WoA machine once for the relatively limited time I used it each day. The noticeable heat reduction on my lap was appreciated.