I flew them both on Sunday. The older MK-1 with the YS 1.40 and the new MK-2 with the YS 91.

I like the lighter new one with the 91. It is a blast to fly a bit wild and then very satisfying to fly as a pattern plane. The shorter wing makes it snap better. I have to change rates on the old one to do a snap. The new one feels like it is tightly connected to the sticks in my radio.

Hard to beat this much fun from a $250 ARF.

I did complain about the pipe-tunnel/pan being pre-cut for ventillation. If you use a YS perf muffler then you don't need the cut-outs. I covered the center join with white Ultracote so that you don't see glass-cloth and wing-wood through the slots..

Also I have been using upgraded YS muffler that has a steel ring around the neck near the elbo. It is solid and shows no signs of leaking or comming loose.

Eric.