I would put a better recoil pad on it. The one that came on my '93 Exp. was harder than heck, primarily made of plastic with a thin layer of rubber on it.
Comparing the two models, according to Remington in 2005,
"Answer
Structurally the two receivers are identical. The only difference will be that the Police model will have a more durable finish. The magazine tubes will be slightly different. The Model 870 Express will have two indents in the magazine tube to accommodate the new style plastic magazine spring retainer. However, this prevents the Express model from accepting a magazine tube extension without alteration to the tube.
Other differences will be that the Police model includes sling swivel studs, a shorter fore-end, heavier shell latches, a heavier sear spring and a heavier magazine spring.
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