I found this Rectimascop 48/2x II Anamorphic Lens on eBay a while ago. Finally I got a chance to test it out on the GH3 and was very surprised by the results.
This lens is from a different time. It has very decent anamorphic characteristics but the entire design isn't that user-friendly for DSLR. I believe they were built for projection, not for filming. However, the "II" of this lens model seems to have a closer minimum focus distance at 3 meters, while the other Rectimascop 48/2x lenses (without the "II") are at 6 meters. That makes it close enough for filming medium shots (see the last two images below).
The most difficult part is focusing and keeping the lens orientation correct. It's difficult to focus like any dual-focus system. The focus ring is quite stiff. When I rotated the ring, it sometimes unscrewed the clamp or slipped within the clamp (I used the vid-atlantic lens clamp). The front part is too big to mount any filters or diopters. I handheld an ND filter when testing. Unless using a matte box with filter trays, a custom-made ring with thread that replaces the front ring or a step-up/step-down ring glued to the front may solve this problem.
The Skier O-Ring is a good match for this kind of front heavy setup. The handle can be repositioned on the 15mm rods to find the best balance point. I wish the adjustable height range of the O-ring and the camera base can be longer for more flexibility. The other thing about the O-ring I wish can be better is the camera plate. The camera would still twist no matter how tight I screw the plate. The two small metal stoppers just aren't that practical for flip-out LCD. Other than these I think it's a very good quality rig.
In conclusion, this Rectimascop 48/2x II Anamorphic Lens isn't really a practical lens for production use, concerning the time needed to get it work properly. For shooting landscape and maybe some medium shots, I think it'll do a nice job. On the GH3, it creates very decent anamorphic images. With grading I can see some very sweet shots there.