I've been thinking of buying something so I could play GBA games recently and as far as I can see, either the 3-in-1 or the EZIV is the optimum choice. I'd be pairing it with my DS Lite and R4, so I'm fairly confident I'd be able to get either to work. There don't seem to be a huge amount of differences, though primarily I've noticed the presence or absence of a card (MiniSD) slot, a compatibility with the GBA SP (or not in the case of the 3-in-1) and a differing price tag, with the EZIV being a little higher. As far as I can tell the deluxe version of the EZIV is either very rare or unavailable, so I'd probably be settling for the original version. I've owned a 3-in-1 previously but the battery ran out extremely quickly, leading me to believe it was a defective model. I've since lost it, but I'm pretty sure the battery itself was evidence of a fake 3-in-1 according to an image I was comparing it to a long time ago, as well as being certain of the battery loss due to being asked to do something every single time I booted the cart up. Hopefully that was just a one time thing, seeing as I practically bought it from the first site I found (this must have been like two years ago at least). I'm slightly concerned about the battery life in either case though, as I want something that would last me for a while (i.e. a couple years worth at least, if that's realistic). A higher battery and as low a price as possible would probably be my main reasons for favouring one over the other. I'm not so sure I'd trust myself to solder in a new battery either; it's not something I've ever attempted before. Just for the record, I live in the UK, in case that happens to affect things in terms of postage, laws and whatnot. I'd appreciate any advice towards which would be best, because I'm honestly clueless as far as GBA flashcards go.