Here's how I did mine. Start with getting a feel for how the plane lands without the flaps. That big wing slows down nicely without them, so the flaps really just act as an airbrake more than anything else. Once you have a feel for how the plane lands when properly trimmed, set about 10 degrees of flap movement and 10% down elevator mix when the flaps are deployed. That's not enough to cause any violent pitching or mess with your elevator trim too much. Shoot a landing approach with the flaps down, and take note what you had to do with the elevator stick to make it settle in properly. Adjust your elevator mix to get the plane to land smoothly with no need for down elevator once some of the airspeed bleeds off. From there, you can add more flap, around 20 degrees, and readjust your mix as needed. Mine wound up near 40 degrees with 17% down elevator. That mix can't hold the nose level if I hit the flaps at cruise speed, but it is just right to make the plane settle in on landing after a nice short and steep approach. It's fun for me in light winds to use them because I can dive at the runway at around a 45 degree angle then pull out and barely touch the wheels to the pavement 15 feet later. That's not proper scale like flying by any means, but it's fun.