The older Express guns don't have the magazine tube dimples that can cause problems adding a magazine extension. Most of the older ones have machined parts as opposed to the MIM parts that some people fear so much in newer Express guns.
Basically the older Express guns are Wingmasters with a rougher blued finish and birch furniture instead of walnut (though my oldest Express has plain grain matte finish walnut). I prefer older Express guns in good used condition, when located at good prices (around here, less than $200).
Today's steel ain't junk, BTW. Workmanship might have been better 'back when' because lots of stuff was hand finished and there was more skilled labor spent on mass produced stuff like firearms. Nowadays no one can afford to pay skilled labor to do that level of work, even if enough workers with enough skills could be found. The 870 is a design that lent itself to modern manufacturing methods, and it still does. QC might not be as good nowadays (1 out of 10,000 with problems from the factory, as opposed to 1 out of 50,000 in 'the old days'), but the 870 design is still a great one.
