Dorian, try this............
+Baby Back or St. Louis Style
+Dry rub of choice
+Wood of choice
+Place ribs on at 275, no need to preheat
+At 1.5 hours, Wrap with heavy duty foil , before wrapping spray a lot of parkay on them and reapply some rub
+Place back on at 275, check BB at 3 hours and SLSR at 3.5 hours with toothpick test, if the toothpick goes in easily and pulls out easily they are basically done. If the toothpick doesn't easily go in and out, put back in and re check in 20-30 minutes. If doing multiple racks, check each rack, they will cook at different rates.
+Add your favorite finishing sauce, any bbq sauce will work while still in the foil, tent the foil, and serve in about 30 minutes
I have tried many different methods, this one seems to work best for me with this smoker. Like you, my ribs were good, but dry when i went at 225 or 250 uncovered.
Let me know how they turn out. Take it easy.