The Meike is 12mm f2.8, and the SLR Magic is 8mm f4.0.
The Meike is probably better, because the lowest aperture is f2.8, so you can step it down to f5.6, the SLR Magic might need to be stepped down farther then f5.6.
Probably doesn't really matter, both would be used outside. The SLR Magic is cheaper.
Except, the SLR Magic, you have to screw down the focus thing, if you change the aperture, you might change focus too. Not really an issue for me, I'd set it to f5.6 or something, and leave it there.
No f5.6 on the SLR Magic. Kind of pointless then, my Olympus 9mm is f8, which is the next thing you can step the SLR Magic down to.
Oh wait, I keep forgetting my Olympus is a fisheye lens. The SLR Magic isn't. It's cheaper then the Meike, so might as well buy it, or have somebody buy it for me.
It's only marked for f4, f8, f16, you can still use f5.6. You just have to be a magician to find it.
Funny, all the bad reviews on B&H aren't verified, even one that says they couldn't return it, because they were past the return time.