I was in a similar dilema a few years ago and thought I'd try a cheap Chinese ring flash from DHGate befor eI spent $$$ on a Canon unit.
I thought that for $70 or so, it was worth the risk, and I am still using and abusing it, and it does the job.
It does the job so well, I haven't even thought about buying a better one, yet.
It screwed on perfectly with my Canon 60mm macro lens.
It also came with various step up and down rings too.
All adjustments have to be made via the camera's menu, but that's no biggie.
Even though it's only about 58mm in diameter, I bought a step up ring to fit my Sigma 150mm macro lens which has a diameter of 72mm, and I was really surprised that there is no vignetting with it (even on my 5D3), even though the opening is so much smaller than the Sigma's front element.