RE: BUSA Fokker Dr1
Fokker Ace, Go for it! I thought the BUSA DR1 was pretty easy to build. It is a fairly large project but all 3 wings are the same basically. The toughest part for me was setting up the wings but it was the first time I had ever done it. My Fokker DVII went much smoother but I think was more complicated. Just be sure to use silver solder on all struts and landing gear joints or they will fail!
I also added a shocked landing gear, as the stock stiff gear takes a real pounding with these heavier planes.
I am sure the VK is a very nice plane but it is tougher to add scale details to a smaller plane. For me 1\4 scale is just right.