Dave,
I've owned quite a few Kaos's and have always been happy with them. I'm just getting back into this after 20 years, and decided on the Seagull PC-9. I read a lot of posts on this and I am installing it with a .60 engine to give it more pop. I didn't know that there was a ARF Kaos around or I would have gotten it instead. I would still plan on using a .60 in it. I like to have the extra power available.
John Dominick