I don't have a Dr1, but do have it's predecessor, the Fokker DV biplane. I got it from 3 Seabees. ARF, expensive, but great construction and finish, solartex covering, 69" span.

It fly's with a positive stab. incidence. The wings are undercambered and develop phenomenal lift.

A friend of mine has just completed a Flair (UK manufacturer) Dr1. It's a little larger then the GP ARF and he is using a Saito 150 for power. It needed a little weight in the nose. A very nice aircraft.

I'll post a flying report within a couple of weeks once it has it's maiden.

Best of luck with those GP Dr1's.