Adam Wilt has written this uncommonly extensive and articulate review of the Rokinon (Bower/Samyang) line of cinema prime lenses, comparing with Veydra and other pricier competitors. Check out his new post at dvinfo.net.
I have the 16mm, 24mm, 35mm and 85mm Rokinon Cine lenses, and look forward to getting the new 135mm one when it’s scheduled to drop in February. They offer good value with high quality after stopping down just a bit, and as I mention in my Blackmagic rigging video, it’s advisable (as Adam notes in his review) to get the Canon EF version for adaptability across (almost) all lens mounts. That also buys you the flexibility to add things between the sensor and the lens, like a variable ND filter or, better yet, a focal reducer to increase your effective field of view and gather more light.