I use a 305 Repo Claron on 4X5. When I spoke with Schneider before purchasing the lens they said that the performance should be comparable to the G Claron provided both lenses were stopped down below F22. They did say that the lens did not have as much coverage as the G Claron. I have never mounted my lens on a Deardorff board to try it's coverage on 8X10. I have always felt that it would not cover. Perhaps I should try it.