Mossbergs are fine shotguns and offer good quality at a reasonable price. Some people will purchase a steel thumb safety to replace the plastic one on their shotguns, and steel trigger groups (available on the M590) can also be purchased for the M500, though unless you're using it for survival in the high arctic, that probably does not matter.
The M500s are fairly light as a consequence of the aluminium reciever, which is not terribly expensive to produce. Since they use either synthetic or walnut stained hardwood, the butt/forend is not particularly costly either (though I have to admit having to replace my M835 forend after it shattered in my hand). The accessories such as three multi-chokes for the M500 or M535s (3.5" chamber), inexpensive smoothbore/rifled barrel combos, the sling swivel studs on newer models and availability of parts/aftermarket assemblies make them perhaps one of the greatest deals out there. The 835 was one of the premier 3.5" chambered shotguns but unfortunately usually comes with just the modified choke tube, though the others can be purchased seperately.
While the super short barrels on the DA Grizzlies or Norinco HP-9s make them especially popular on this site, the basic M500 and M535 shotguns come with three chokes for less, and in the case of the M535 smoothbore/rifled bore combo cost about the same or even a bit less than a standard Grizz or HP9. That would make a perfect beginner's shotgun and would suffice for most hunting situations, though I'd probalby add a centrefire rifle and .22 to a basic hunter's arsenal.
Sure, the milled steel reciever or nicely finished/checkered walnut on an 870 Wingmaster are nice to have for a couple hundred dollars more, but for most hunters the Mossberg is fine.
If you want to save even more money, there's an economy version of the Mossberg called the Maverick. The home defence model or normal length, vent-ribbed version with modified choke tube go for about $200 and have gotten decent reviews from most users on this site. Not every reliable, inexpensive gun comes from China, lol!