Quoted:
I know you would. I'm an 870 armorer myself. The 870 is OK, but it does nothing better than a 500 (or 88) or 590 and the (modern) 870 is no longer the shotgun that it once was (crappy finishes and rough barrel chambers). Add in the dated design (the control layout is relatively awkward) and construction (riveted ejector and brazed magazine tube that mandate a trip to a gusmith and a refinish in order to repair? GTFO) and there's no good reason to not look elsewhere. The only 870 trait that I prefer to the 500 is the two-pin attachment of the trigger group. Frankly, the only ting keeping the 870 alive at this point is tradition and nostalgia ("An even better solution is a nice, sexy trade in 870.")
To be honest, I disagree with nearly everything you just said.
In my experience with LE shotguns, the 870 is a far more robust and long lived choice. Yes, some of the portions are harder to work on like the mag tube, shell latches, and ejector. It is my opinion, however, these design features lend to the platforms overall ruggedness. I have to work on out 870s far less than out 500s and 590s. The control layout is something I prefer on the 870 over the 500 series guns, and do not find it awkward.
The newer guns are somewhat weak sister when compared to the older ones. They are still good guns, however. We have had one issue in the last 50 870s we got, half of which were 14" Police guns, the other half Expresses. The one problem child happened to be the 14" Police that was issued to me, and it was quickly remedied with a forearm tube swap. The 500s and 590s they replaced were wrought with problems from the day we got them. I personally do not feel any pump shotgun has approached the overall quality of the 870 design, and if one does manage to dethrone it, the Mossberg definitely isnt it.
We each have our own opinions, however.