Here's one more example using this technique.
When the Sky Rolled Back by Thousand Word Images by Dustin Abbott, on Flickr
For my taste, that part around the sun is very strange. There are some kind of halos or something like that. I see that in my case too, when I was merging several exposures in Photoshop's HDR Pro. That's the reason why now I prefer to blend exposures manually by using luminosity masks. Especially when you have straight horizon, it's quite easy to do.
And there is quite a lot of "ghost-ing" around the clouds, too.
Otherwise, it's nice image.
The area around the sun is due to the MKII's inability to natively bracket 3 stops in both directions. I never have similar issues when shooting with my 6D, but you're right about the way to rectify it.
I initially thought there was some ghosting around the clouds, too, but that is actually the way that the clouds were.
It looks the same in single exposure files.