I used this tank a few times, without any problem. When loading, attention shell be paid to the emulsion side of the film. Load tank with the emulsion looking inside of the film curve. This way emulsion didn’t touch any metal surfaces of the cage and developing will be even. Also, as I noticed some people successfully used rubber band instead of a zig-zagy metal band, but I never try this because I have a metal band.I had a problem only once, when first time used this tank, and loaded it without attention to the emulsion. The negatives witch was loaded with the emulsion facing to the outside of the film curve was ruined. If you will practice to load this tank with lights on, you will see why uneven developing happens. Film when loaded always have a contact with the metal parts of the cage from the outer side of the curve. But in the same time the inner side of the film absolutely free of any contacts and will be fully immersed in the developer.