I've never used miles for upgrades. I've traveled with my family to many places around the world in Y. If we had done it in Business, we would have made it to about half the places and run out of miles.

I know some here find it hard to believe, but we actually survived coming home from Istanbul (11h) in Turkish Y and round trip from Sydney (14h) in American MCE.

Yes, I've enjoyed seat 27K on an Emirates A380 on several business trips, but not at the expense of being able to travel and see the world with family.