I love the brush also. I just wish they would make the shaft a bit more stiff, (no this is not a Viagra moment), it bends a bit too easily. If you get a bit crazy with it you will find your arms peppered with black dots, so be prepared. I can really get back into the inner wheels. For the engine its great too!
Cheers,
GREG
I too ran into this, but adjusted my technique and now all is well. Since I know a a few guys have broken theirs right above the handle, I'm pretty careful with mine. I think I heard or read somewhere that a newer version has or will have a sturdier shaft. (Stop snickering!)