"...I'd recommend NOT getting a shotgun with a huge magazine. They just seem to make the gun too long and heavy..."

Good point. I once put an extended mag on my 18" 870, loaded the thing up, shoulder it, hated what I felt, and removed the extension. I then added a side saddle (the six round model), and am very happy with it. I have been thinking about a speedfeed stock, but am in no big hurry to part with more of my hard earned money...