Mithcell's is good -- definitely better than many run-of-the-mill ice cream places -- but as someone who grew up with Malley's fudge sauce in the kitchen, Mitchell's lackluster fudge sauce taints their whole sundae for me. I'll still get their Turtle Sundaes from time to time, but only if Malley's fudge sauce (and whatever extra fatty things they probably put in it to make it taste so good) isn't available first.
Very nice service, and fast.