The maximum size Ilfochrome Classic prints I produced from 35mm (transparency) was 46x30.5cm. Beyond this, the optical fall-off is too pronounced.
I wouldn't besmirch Rowell's substantial body of work that still gets people running for the cameras trying to imitate him. His records of the landscape were inspiring, and often imperfect, but he was the right person there at the right time and made the name and product for others to look up to.