I agree with Aero, the R4 is outdated, furthermore it was never that great to start with. It was rather tempremental at being seen (took 5-10 attempts usually for it to go to the R4 screen instead of the standard nintendo DS screen saying "No card inserted").
It also had a tendancy to crash at random, and that chance increased exponentially if you closed the DS putting it into standby then opened it up again. It also just hated some games and crashed every 5 seconds with them.
DSTT was aweful, it would work great for about 5 attempts then it would stop being recognized ever again (i tried like 20 times, then reformatted the SD to get it to work again, then after the second break tried again 20 times then ditched it).
So now i'm using the EDGE card, which i must say i'm very happy with. Moonshell is optional, freeing up a little bit of space if you don't want it, it loads every time and i've yet to have it crash on me. Only really complaint about it is that a spring loaded system for the SD slot would have been nice instead of having to claw at it to get it out once it's in.
So yeah, i'd go for an EDGE, i can personally reccommend them, or give one of the other cards Aero reccommended a go. Good luck
