Can any users out there give me their opinion of the Osaka Commercial lenses fro m Bromwell Marketing? I am particularly interested in the 400mm and 500mm tele designs for 4X5. The bellows draw, the weight, and certainly the price make the m intriguing. But how do they stand up optically? Can you compare them to the Nikkor teles or the Fujinon 450C? Thanks for your feedback.