I tried this stuff in a Lab-Box last summer and got terrible results... mostly crossways marks on the film from uneven development. The developing action happens so quickly that even small irregularities result in non-uniform development. Tried it again more recently, though, and it was fine... the only thing I did differently this time is that now I soak the film in water for 1 min. before I start the developing process. My theory is that pre-wetting the emulsion makes it accept the developer more evenly. But I've never heard anybody else complain about non-uniform development, so it may just be another example of PCTHOM (Photography Curses That Happen Only to Me.)