I had a 3000 when they first came out and got rid of it because of poor dealer and S&W service and the complete lack of replacement barrels. They are NOT a copy of an 870 so forget about parts swapping.
Yes, I heard the Mossberg story too but even they don't seem to have any barrels and for years I couldn't find one (when I complained of it shooting low, S&W just bent the barrel up. It looked like a ski jump).
I would have to real cheap, in excellent condition and exactly the configuration I wanted in order for me to buy one. Other wise I'd look elsewhere...