I've been playing with a Canon EOS 100/2.8 macro lens (the non-USM version) and some extension tubes, and finding that I end up working close enough to the subject that a conventional flash doesn't work very well due to the lens shadow. So I'm pretty sure I need a ring flash.

The Canon ring flashes are pricier than I can justify, but there are some inexpensive Phoenix models. Online reviews are wildly split between "wow, this is great!" and "this is a useless piece of junk!", which isn't that helpful.

The Phoenix RF46 seems to run about US$90, which I can countenance spending. For that price I don't expect Leica workmanship or extremely high output, of course, but if it works as advertised---fires when triggered, doesn't fall apart under normal handling, works with Canon TTL modes---then I'd be happy. Has anyone worked with this flash enough to shed some, er, light?