Bill,

Maybe it would be helpful just to see the ballpark in which your stall speed reduction might be. Flaps reduce stall speed by increasing the stall coefficient of lift (CL). The stall speed is inversely proportional to the square root of the stall CL. If you were able to double your stall CL by using flaps, your stall speed would go down by 1/1.414, or a 30% reduction. There is little chance that you will be able to double your CL with flaps, so your landing speed reduction will be less than 30%. If your flaps give you 50% higher CL, your landing speed reduction would be about 20%. If your flaps give you a 30% increase in CL, which is getting more realistic, then your landing speed would be reduced by about 12%.

Good luck,

banktoturn