As you have pointed out, there are trade-offs. You are talking about the high end of the MK-III family. I regularly hunt squirrels with a long barrel MK and carry one extra magazine. Personally I would not exchange it for a SA revolver.
One thing that concerns me about the Single Ten or any multiple round revolver, is the potential of losing, "Timing", especially as it wears. I had a DA-Nine and the machining really get fine. ...
Be Safe !!!