If you prefer something other than profiles or "fun-fly" planes, believe or not, a simple Sig 4 Star .40 will flat spin VERY well, even with the stock CG. You will have to go to near max throws on the ailerons, rudder, and elevatore, but with mine, it is very easy. First, enter a conventional upright spin, with trhottle at idle. Then, once the spin is established, slowly start to cross the aileron, as you bring the throttle up towards full at the same time. By the time the aileron is fully crossed, you should be at full throttle, and the thing should be in such a flat spin it looks like a Canadian Maple leaf falling slowly from the sky. You can try just throttling back and releasing the stick to exit, but I have had better luck by FIRST un-crossing the aileron (aileron moved back to the same position as the rudder) until the nose drops and the plane resumes a conventional spin. Then all you have to do is let go of the sticks, and it should pop right out into a nose down dive.

Lee