Well I finally got my EZ4 and I have to say I'm very impressed. The only "problem" I seem to have is that the case doesn't close completely together but once it's in the DS I don't care.
I have no problem pulling out the memory card. I had more trouble getting it in and out of the SD adapter than the EZ4. I really think a lot of the problems are just a result of microsd being SO small.
I'm not sure I got the "old version" of the superkey because the box and label say "for nds & ndsl". Also, I didn't update the loader. Everything worked right out of the box.
All in all I'll say that I'm satisfied with the card and the superkey. It looks good and plays the roms without giving me any problems, that's really all I care about.