I've realized that there are two models of cassette cases: One with "round" edges and another with "square" edges (hope you understand what I mean). In the first type, the cartridges fit with a bit of pressure (this will destroy the cover with use), while in the second, they fit perfectly.
I've seen on eBay that some people sell pinless cassette cases, but I've none of this kind to check how a cartridge fits in it. Could anybody help me, please?
Thanks in advance.