I'm posting this as there's always lots of discussion and wonder on the CN reflector forum as to whether or not a person's dob is performing as it should. I thought I'd share what I see so other's might get a better idea about their own scope.
The picture below is an accurate representation of what Jupiter looks like in my 10" reflector when it's ABOVE 30 degrees elevation and the seeing is very good (P 8 -10).
Things to notice are the blue festoons in the EZ, detail in the cloud bands and the GRS, and some barely discernable white ovals in the far north and south regions.
I would say my scope is at least diffraction limited from the testing I have done, and I always keep it precisely collimated and cooled to ambient before use. Needless to say, I'm looking forward to Jupiter climbing up above 30 degrees elevation from my locale. It's been a long time.