I have them installed in a 1/4 scale Balsa USA Fokker DVII, a Great planes Ultimate Bipe 1.60, and one is going in a 1/5th scale TA 152. The TA 152 is getting finished up as we speak. I even have an original DL 50 installed in a 1/5th scale sport Mig 3. I am building a Ziroli Stuka that has one that has been installed, but I need to buy another one for this airframe when I get back to finishing it. The rear exhaust configuration alone is worth it IMO. Not to mention, you can use the stock muffler, without having to drop another $80 or so for a Pitts wrap around, that will come loose without modification.