A few years ago I was talking to a Denglas rep, and he compared the Denglas coating, which he said the glass was dipped into during manufacture, to the Tru-Vue Museum coating, which he said was sprayed on. If you hold the glass up to a strong light and look very carefully, you can see the difference.
I use Tru-Vue Museum, and until then I never noticed the coating patterns, and more importantly, I never noticed any patterns or banding showing on the print. I continue to use Museum glass because Denglas is very difficult to find here. Unless I look very, very carefully at the framed print, and in a certain light, I can not see any patterns or banding.