FOREND WILL NOT FIT ALL 500's RIGHT OUT OF THE BOX.
Okay now that I have your attention, here is the reason so many are complaining (and rightfully so) that the Hogue Forend will not fit their action bar.
This forend is designed to replace Mossberg's that have the existing 7-3/4" slide tube. That is, the existing forend is mounted on a tube which slides on the magazine tube, said tube is 7-3/4". OK now, Mossberg 500's have 3 separate ways of mounting the forend to the shotgun. First is the 7-3/4" tube, which will require nothing for this forend to work. Second, it will have a 6-3/4" slide tube which will require Hogue part # 05020 which is an adapter for the shorter slide tube. In some cases, it will also require that you grind down some of the ribs in the new forend to accommodate the adapter (the one i received had the ribs pre-ground). Third method, there is no slide tube. The forend on the shotgun is a forend/slide tube combo. This will require you buy the new factory slide tube (from some place that sells Mossberg factory parts like Brownells, Mossberg part#12362BL, Brownell's Part#631-000-295. This is for the 6 3/4" slide, as it's cheaper than than the 7 3/4" slide with the locking nut.), and the Hogue adapter. To replace the slide, you will need to completely tear down the shotgun as the slide is one of the last pieces to be removed from the receiver.
A second word of advice...If the gun you are putting this on only has a pistol grip (ie the Persuader)be advised that there is NO stock bolt or lock washer included and you will need it. These are easily found on Midwayusa, Brownells...etc...
Or you can simply call Mossberg @ 800-363-3555 and in the past they have more than happy to send you one free of charge (they even include a new owners manual)
Pros: Tacky surface, shorter LOP, looks fantastic (mine's the OD Green)
Cons: The fact that additional parts maybe needed and are NOT included.
This review was written in the old system and had content requirements that are different than reviews written today.