Hi Ben,
No, it stumble coming off idle and doesn't want to do something else before it's warm. I tried smooth and rapid opening. Like too much something (fuel or air). But when it's warm, it runs perfect. Quick answer, good idle (500rpm) smooth and no vibration. I'll try do take a video next time I fire it.

I use unleaded 95 E10 fuel, as it's almost the only choice I have. Maybe it doesn't like it ?