I will post a video of my flight with the other warbirds as soon as I edit it down to an upload size for youtube. You will see that it is no slug in the air. It is possible that the planes you have seen are using the manufacturer's CG which ,for my plane turned out to be very nose heavy. After I removed 1/2 lb. of nose lead and moved 14 ounces of batteries from the firewall back to the wing trailing edge I was able to take out most of the up trim it needed for level flight. Nose heavy planes have to fly at a higher angle of attack which tends to make the flight performance sluggish and limits top speed and control responce. My plane is very light on the controls and its slow flight is way slower than my TF birds, landing speed has been described by other club members as "walking speed".
I have included a link to a short video of some of my landings I made for another thread. Some of the landings are of the H 9 P 51. Keep in mind that most are in high cross-wind conditions but you can compare the difference between the TF and the H 9 planes in landing speeds. The older TF D model only weighed 21 lbs. so it is flying at the ideal weight for that plane. The other TF plane weighs 29 lbs. and the H 9 Mustang is at 27 lbs.
https://www.youtube.com/watch?v=sy2utXwbCgw