Dennis, which MES do you have again and which Generation? I'm too lazy to look all that up. I'm asking because as I posted I'm having no problems with my AMNPS.
In the MES I've seen no need to turn the ribs. Yes, the smoke is coming up from the bottom of your smoker but it's also in a relatively small, insulated enclosure which means it's filling and circulating around the inside of the smoker. I don't turn my ribs at all. Think about it: the heat source is also beneath the ribs but the tops of the ribs still get fully cooked and develop bark, right?
My ongoing problem is mushy ribs although my wife likes them that way. To combat both her tastes and the ribs, I'm going to cut the cook time (for baby backs) down to 4 hours total at a cooking temp of about 235-250°. Can't remember who first talked about it here but I'm trying 2-1-1 next time because I still believe in foiling ribs. The 2nd change I'm making is no foil juice. Pork ribs secrete more than enough of their rendered fat as grease/juice inside the foil so adding extra liquid to this just serves to make the ribs mushy. I don't a lot of bark which is why I'm also foiling. I guess another way to keep thick bark from developing if I want to cook the ribs naked would be to go very lightly on the dry rub.
I just decided here and now on my next ribs experiment. I always smoke at least two racks of ribs. Next time I'm going to put the usual amount of dry rub on one rack and foil that. For the second rack I'll do just season the ribs with salt and pepper and smoke it naked. When the time comes I'll report back on the results. It'll definitely be another learning experience and I hope a tasty one.