I picked up a B's4x5 second hand. It worked fine even with my dilute developer. The only issue I had is that it is hard to clean in the corners compared to the SP445 flat film holders. Do not put photoflo in either tank. It tends to adhere to plastic and can affect your next batch. My patterson tanks are also slower to fill and dump than the SP tank, but with my dilutions and slower processing times I did not get uneven development.
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