The Zeiss Jena primes are quite sharp, even wide open, are neutral in color, and medium contrast, with subtly textured bokeh. They are truly made to shoot wide open. Their coatings are saturated amber and purple, and the results are lens flares that are controlled but with lovely character. Although “MC” stands for Multi-Coated, these coatings are nothing like the well know Zeiss T* coatings. They have virtually no chromatic aberration. 
Iron Glass’ housings are very high quality. Focus and iris are buttery smooth. Focus rotation has been expanded to a generous 300 degrees, and close focus has been improved dramatically, including an impressive 8” close focus on the 35mm. They all are compact, lightweight, and have matching 110mm fronts, and matching gear positions across the set. These are compatible with film cameras, and they are sharp enough to get excellent results on film.