AT 91, AT 91R, AT 3600, Rega Carbon are from the same family . The generator is same with a few variations and the stylus body is also interchangeable. However the VTF and stylus cantilever are different. This has a bonded spherical stylus. Also 3600L is the heaviest tracker and is OE in many lower cost tts such as AT LP 60 and Denon DP 29F. AT 95E, on the other hand , is an elliptical styli cartridge which was found in middle range tts such as AT LP120. Now AudioTechnica has introduced the AT-VM 95 series which have a large range of styli ranging from conical to Shibata. I have used the AT 3600L and, without stirring up a hornet’s nest, this is a good cart for my old Bollywood and scratched English records! I prefer it over many more expensive carts in my collection. I track it at 2.5 to 3 g. Owning both Japanese and Chinese Versions my opinion favours Japanese. Can’t pinpoint why!!