Hey John, I don't know if this page is up to date, but Bushranger apparently have a line of trimmers powered by Kawasaki.
I have a 43cc Kawa powered Shingu brushcutter and it's an awesome engine. It's almost due for replacement and I was looking at the 40+cc Shindaiwa, but I'll check if the Bushranger/Kawa are available first.
I have the 33ccMitsubishi on my Atom Edger and it's a nice engine, but gee it's a cold starter. It fires up easily, but have to leave it idle for a minute or 2 at half choke before I can rev it out.
Have the 25cc '5' series Husky for general use and it is surprising how much power it has. The brushcutter doesn't get loaded on nearly as much these days.