BPF - Fullwings has described the pitfalls of the ASW20 in excellent detail. Assuming you get a good one, you'll be impressed with how pleasant and easy it is to fly. But after a very short while you will go home disappointed. Why? Because unless you are mentored through the next step, you won't be able to use the performance which will lead to frustration. Let's make no mistake, we are talking about a cross-country machine. To knock a hole in the sky in it or using it just to do circuits would be like using a Ferrari to store coal in. You already understand weather, wind, clouds but you will his have to learn about them generally from underneath. Gluing wave, ridge and thermal lift together will take a few seasons to learn. The best way to learn will initially be on lead-and-follow trips and then possibly a competition or two. Regarding the landing flaps, even though your field is long, how long will the field you land out in be? And would you prefer to land in a field you haven't surveyed at a high speed or a low one? But having said that, the landing flap in the ASW20B is more than adequate.
PM