I suspect this one is some sort of modified version of Olympus AIR. If that's the case, they can probably modify Sony's QX-1 too, which has bigger sensor, APS-C.
Here is an comparison between this lens and Sony Zeiss 135mm f/1.8 APO lens from a Korean beta-tester. The Zeiss lens is a Sonnar, not Planar, though.http://lcap.tistory.com/entry/Samyang-135mm-f2-vs-Sony-ZA-135mm-f18
Top: Samyang, bottom Zeiss.
And this one is comparison between this lens and Canon 135mm f/2 Lhttp://lcap.tistory.com/entry/Samyang-135mm-f2-vs-Canon-EF-135mm-2-L
Here is a Korean beta-tester's comparison between this lens and Canon 135mm F/2 L, Sigma 70-200 F/2.8http://www.slrclub.com/bbs/vx2.php?id=user_review&divpage=6&no=40970
As you can see from the chart, this lens is clearly better than the other two from the f/2.