<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by Roger:
miles earning and redeeming rates are different - check on this in the online handbook, as it may be relevant to your circumstances
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and that's the point.
Once you start extracting one comparison, you end up with others and the whole topic gets out of hand. (For example, some awards 'cost' more and some less, Concorde is only 3x mileage, there is a 20% miles reduction for awards for much of the year, points and miles are awarded for a much greater range of fares, etc etc)
Compare the lot and decide!