I just bought a used police/military 12 ga. It's in great shape. It's the standard model w/no ghost rings. I bought it for $250 out of pocket ($225 for gun and $25 for registration). How did I do? Any info on this shotgun is appreciated. Is the 590 better than the 500? and lastly, how is it compared to Rem 870s, Win 1300s, other military type shotguns. As always, any info is much appreciated. Thank you.