This review give the nod to Olympus 35mm shift over the Nikkor, and the Leitax conversion is easy. http://www.16-9.net/lens_tests/35mm_shift/35mm_test1.html
I actually have the Oly and the Leitax adapter, but my copy of the lens needs adjustment because the infinity stop is off so it won't hit infinity focus properly, so I can't give you my impressions (I have confirmed with other Oly lenses that the fault is in the lens, not the adaper, and by mounting on crop bodies with adapters that let you focus past infinity that this is indeed the issue. . If you go the Oly route, be sure you get the later (and much rarer on eBay) multicolored version.