Why a 20 gauge?And are you against an auto?
Dont get me wrong. My first gun, and I still hunt with it occasionally,was an 870LW Wingmaster.And I love that gun.
That gun kicks harder than a 12 gauge 1100. Light weight and fixed breech make sure of that. If your finances allow it, I would be looking for an older 1100 20 gauge, or maybe some other gas automatic.That is if it is for recoil reduction.
My daughter, who was all of 4'6" tall and weighed about 85 pounds, 11 years old CHOSE a 12 gauge auto after shooting a youth model 870.She shoots a Mossberg 5500 GAS auto, 1" shorter stock, 22" barrel.And still has no desire to change guns at 22 years old.She has shot ducks, geese, pheasants, quail and grouse with it.
More loads available for it than a 20.
If you are against an auto,
Then I agree with the rest.
I dont think there is a better gun built in the 870 Express price range.