I have a Sig 4*-40 ARF for xmas (after a summer on a TH trainer) but was starting to think a build would keep things interesting over the winter.

I had thought about the third plane being a Sig Mayhem 3D or U-Can-Do 3D but neither come as a kit.

SSE might be an option but I have not decided on 40 vs 60 size and SSE only comes in 40 (and what seems like a fairly small wing length).

So the question is what would be a good 3rd plane option but also a build first build option?