Advice from an old f(a)rt -
Go Remington! Yes, I did have a Mossberg 835 and for only one season. My first magnum shotgun was a Wingmaster that is probably older than you are. It is in such good condition my son wouldn't use it when his shotgun was not working right. He had a problem with the slide not functioning on his 870 Express Super Mag, but that was from an assembly issue from when he had it camo dipped. He shoots many shells every year and has never had a problem.
I believe most of the issues with the Express are from people comparing it to the Wingmaster. The differences are more like a Chevy and a Cadilac. Both are fine cars and both are fine guns.

Here's a picture of his 870 after being dipped.