USAir's dividend miles program is so full of blackout dates and premium dates (which require a huge number of miles) that it's almost impossible to use them. I tried to book a ticket from Chicago O"Hare to Portland,OR, more than 3 months in advance, and I knew the flights were less than half full because I had selected seats for a purchased ticket, but the very rude "customer service" agent said there were no seats for the lowest level of dividend miles.
When I started asking about it, he basically hung up on me. This after I had to keep asking over and over what he was saying because his English was so poor.
So do not use this as your frequent flyer airline, and do not fall for their bogus "get a free round-trip if you sign up for our credit card" on-board scam.