Well, after a couple weeks of tweaking, hacking, and rebooting my A1200 trying to get various demos and games installed via WHDload, my success rate is about 50%.
Many games (future wars, neuromancer) refused to run and just crashed my machine. State of the Art still doesn't work.
Maybe it doesn't like where my accelerator maps memory, who knows.
In some cases I could adf2disk to a disk image for installation... but dms write to my virtual disks always fails, unless I use FMS, which doesn't allow inserting and removing disks on the fly.
So my opinion is that overall, WinUAE is MORE compatible than just one Amiga, while the overall experience and "Amiga Feeling" you get is better on the real machine.
So I still like playing with the real thing... but it's frustrating at times.