Yongnuo 2.0x TC
whumber, thanks so much for posting those shots. My Canon 2x Mk II died recently and funds don't stretch to a Mk III so I'm going to go for a Yongnuo in the meantime until the Mk III second-hand prices drop a bit*. Your post give me the confidence to give it a shot from Amazon.
* Here in the UK a second-hand, unboxed, Mk III is still over twice the price of a new Yongnuo.
* Here in the UK a second-hand, unboxed, Mk III is still over twice the price of a new Yongnuo.