Stall speed is related to wing loading regardless of airplane size. A simplified estimate of stall speed is 4 times the square root of the wing loading in ounces per square foot. Thus, if your wing loading is 35 ounces per sqare foot, your stall speed is approximateley 4 X 35^.5 or about 23.7 mph. Flaps only lower this number slightly. The real benefit of flaps is that it lets you safely approach this speed without risking a tip stall in addition to making the plane a little more draggy for a steeper glide slope.
This formula predicts the stall speed of even full scale aircraft with surprising accuracy.

While big birds may fly more smoothly than small model aircraft, they do fly faster even if it doesn't look like it. That's the reason I try to talk newbies out of making a giant scale model their second plane. They may be smooth and easy to do "grease job" landings with, but, because of their higher touchdown speeds, a pranged landing will mean major repairs, not just bending the landing gear straight again.