While i love to stand on theground and watch airplanes take off and land,flying in them is a total different story. I like DC-9,and its cousin the MD88 inside seat configaration. There is only ONE middle seat across the rows,so there is a 4 in 5 chance you have a window or an aisle. Its my personal opinion,on why AA is popular with business travelers,because of their MD80s.
By the way,if you do your research into aircraft maintenance,A,B,C,D checks,you will see that theoretically a plane can fly 20,30,40,years and still be like new. The problem is that it is more expensive to do maintenanance on them. But lets look at from the airline perspective.....A 20 year old or more plane is PAID FOR! While we like new aircraft,just like new cars,they have payments,and older aircraft becomes a cash cow! The only thing the airline pays for is the crew and maintenance. All those AA MD80s bought back in the early 80s should be nearly paid for..ching,ching. Something to think about before you go bashing older aircraft.