In all honesty, I have no idea what the mileage was like at stock nor as it is now. I fill up and drive it, I don't take any notice of what it uses, sorry I couldn't be of any help mate.I don't have any experience with ProTorque converters, but I put a precision industries 2800 stall in my last car, and it really woke it up. I think the 2800 rpm stall is the perfect amount for a street car, and it should not affect your mileage too much, if at all.
Jected...did you notice any drop in mileage after the install?