I hate to say it, but again, if your going to spend that money... spend an extra $20 bucks and get a browning or benelli... You'll be mutch happier.

As for your actual question... I think the 870 is a more durable gun. Three of the guyz at my deer camp hunt with 870's and two with mossberg 500's. These guyz with the 870's put those things through hell and they still work like a charm. They pump losens up a bit on them but i guess thats pretty common. With the mossberg 500's (which have a very similar action as the 835) the pumps have a lot of twist to them. My father-in-law has the 835 ultamag turkey special (or soemthing like that) and he loves the gun except for the tang safety. He says when he click over the safety while turkey hunting it's too loud.

The stock is a bit short on the 870. I think it's good if you do alot of hunting with your winter coat but for me, i think i couldn't do much upland shooting with a stock this short. It doesn't seem to swing for me well at the range.

I like the grip and the forearm on my BPS. It's a lot thicker and feels better in my hand then the 870 or 835.

Anyways, these guns you mention kind of have different purposes, the 870 being more of an all around gun. But, they can both be pretty versitle. All in all, i'd say get which ever one fits you better!

Good Luck!