I don't have any input on the 500, but I've been shooting an 870 for 12 years (the same one). Can't beat it in my opinion. It's been on the bottom of lakes, beaten on boat rides, and used as an oar and still haven't needed to do any repairs. I just won an 887 so im going to give it a try this year. From what I hear you should be happy with eihter choice.