Whew!....
We use them too. Of course the air-miles we have accumulated aren't always as good as it sounds...some days they are full with "paying" customers. Of course, we change our plans....or....Pay and get the seat we want. Amazing how fast those seats open up then... Oh well, doesn't matter. ( what good are air-miles if you don't get to use them?)
We've played it every way possible and it doesn't matter, we still travel....and pay to exit one way or another.

This was just an informational post.