I used a panel made in 1975, in 2012, and it still put out it's rated wattage. A 37 year old panel. Why would anyone replace working panels that still have so much life left in them?
Dark blue encompasses most mass produced commercial panels. Notice there's no change since 2008, and even a modern panel is only a few percent more efficient than the one I used from 1975.
Were you just guessing?