Is the Rokinon (Samyang) 35mm f/1.4 US UMC Lens sharp? This page visually answers that question. Shown above are 100% crops from a lab-captured 35mm f/2.0 test image. Observe the contrast and resolution of these results.
Is the Rokinon (Samyang) 35mm f/1.4 US UMC Lens set to 35mm f/2.0 sharper than the Zeiss 35mm f/1.4 Classic Lens set to 35mm f/11.0? The image quality comparison above also answers that question. Switch between the results to see the sharpness differences between these lenses.