Well, let's say "similar", rather than the same. There is quite a collection of plactis in the trigger group of the Express as compared to the Wingmaster. The bolt of the Express is finished with the gun, rather than chromed like the Wingmaster.
I have 2 of each, and my Express's hiccup way more than my Wingmasters. When we're talking about a few hundred rounds for each gun on a given day, I have to make sure my Expresses eat only long base, while my Wingmasters will eat anything. The Expresses do not like fast follow-ups.
That's been my experience, and I've had some kind of 870 since the late 70's.