when to put sauce on my ribs??

I sauce mine the last hr of cooking my .02

No real difference in tenderness.

Only taste difference is the smoke and heat will have an effect on the sauce, either carmelizing any sugars or giving some smoke flavor.

If you're smoking them to eat tomorrow, just sauce them when you warm them up.

In fact, sauce 1/2 the rack tonight and the other half when you eat and see which way you like them.

I have 2 racks in so I will sauce one and leave one dry. Thanks for the replies, this forum is a great thing.