I have a lot, and I mean a lot of old Gameboy games lying around that I want to play but the only Nintendo handheld I have is the 3DS XL, so I've been downloading the roms and playing them on an emulator but then I remembered using an R4 card years ago. I'm still confused as to what exactly it is. I know it's basically extra memory, but can I play DS/DSi/Gameboy Advance/Gameboy Color games on my 3DS XL by downloading the rom from emulation website and then putting it into this card? If so, is this what I should buy and is this a good tutorial for learning how to set it up and download games onto it? I just want to make sure this is the right thing before I buy it and expect to be able to play old games on it.