GW means GoldWafer (card). You can use it like the FUN card. It will do the job, only FUN you can find more use for. For example updating Matrix CAM. EMU is often used in connection with Humax 5400, CAMs and other patchable receivers. Raughly it means emulation because these devices do not have specific hardware for all encryption system but their hardware programmed with the right software allows them to emulate (act like) they do. Humax 5300 is patchable too. The problem is that it is missing one very important chip that 5400 does have. I believe it would be possible to make an EMU soft for at least 2 or 3 systems on 5300 but there are so many other devices like 5400, Dreambox and shed loads ;) of CAMs that the people who could do it simply can't be bothered. Humax 5300 is therefore dead unless you use it with a CAM.