Hey, bumping this topic because I came across some information which is somewhat relevant regarding memory cards.
I always bought 1st-party Official Nintendo brand memory cards because we all know that they're the best, right? Except they aren't, and it doesn't matter. Here's why: those official cards I bought are not really Nintendo brand after all. They're apparently cheap imitations.
I found a thread (http://www.gc-forever.com/forums/viewto ... =26&t=2474
) where this was discussed, and it got me curious. So I broke out a tri-wing screw driver and disassembled both of my official Nintendo brand memory cards. Both of which came new in factory-sealed packaging with Nintendo's Seal of Quality. One was bought at a shop locally many years ago and the other online more recently.
While the outer casing of the ones I own and use are very nearly identical to official cards, the internals are certainly not. Without taking your cards apart, the only tell-tale difference is that legit cards would have a circular depression with a raised dot inside on the underside of the card just to the left of the Nintendo logo near the bottom. Neither of mine have this. If you do take them apart, it becomes obvious which are real or not because the actual ones have Nintendo's trademarked logo printed onto the PCB, as well as DOL-64MC for the legit 1019 block version. Neither or mine use Samsung chips, either, though one did have a recognizable Chinese brand I have seen elsewhere (Newegg I think).
Anyway, none of this matters because neither have ever failed, and one of those being after several years of use. Moreover, I believe that based on my personal findings, it is very likely that the majority of memory cards in use are probably not official ones.