Blowing smoke. I have several Mossy 500's from an original design with the single action bar (60's era) to a newer one (late 90's). The only thing that rattles is the forearm if you shake it due to the slides. There are only 2 sticking points of the mossy 500. No mag extensions for the tactical guys, and the trigger assembly is plastic which is the weakest part. The actions are solid and have great lockup and I have never yet had the issues of small plates of metal bending and causing jams (870's biggest issue). I have shot thousands of rounds thru my Mossy's from trap & skeet shooting I cannot complain as the factory mossy seems to fit me perfectly.
I also have a remy for those thinking I'm against remmys. Great shotgun too, more widely available accessories, far more customizable. Just jams occasionally.
Now if you go to the cheaper Mossy versions (Maverick 88, etc...) They may be made cheaper, I do not know.
I myself like the Mossy over the Remy. Would I ever say "you couldn't pay me to own one"? Hell no. I'll take a Remy to shoot anyday. I just happen to like the Mossy better for feel and a solid action.
It's the same thing as asking the Win 94 vs Marlin 336 debate. Everyone has their own opinion, some just more biased than others. Try them out if you can. Decide what you are going to do with it. If It is for tactical games, Remmy is probably the way to go because of the extra customizability, but for waterfowl/clays/birds/deer/etc... either is just as good as the other.