I have the US 60 kit waiting to be built. From reading the instructions, I can tell you it is a little on the more "old school" side of kit construction than something like a Sig Somthin Extra but that's not necessarily a bad thing. Could you build it as a first kit? Heck, I don't know. If you have a knack for building things already, followed the instructions and got advice from others who have built the plane, I imagine you could do just fine.

I've never flown an Ultra Sport yet either but plenty of people on here swear by it. Go over to the kit building forum, you'll find a couple active threads on the plane.