Yeah, it all depends on how much money you're willing to spend. The only flash cart I have is the DS-X, and I have something like 14 games on it. If you were to get the R4, along with let's say a 1 gig microsd card from amazon for like 20 bucks, then you could store twice as much for about 70 dollars vs. 125. However, the only real important game that doesn't work with the DS-X is Animal Crossing. I don't know too much about R4, but I do know that it has good compatibility. But if you read the review, the Download Play/Multiplayer features don't work very often, so if you have some friends with DSes, you might want to consider getting the DS-X, as that works pretty much all the time, even with DS-X to normal DS Card. You might want to get a slot 2 device like M3 Lite/M3, cause they can play GBA games, and do some stuff that slot 1 devices can't. If it were me, it all depends on if you are really willing to spend 125 dollars, but it's an awesome cart, nevertheless. I'm sure you'd be happy with R4 too. M3 Simply's similar to R4, but is out of stock at most stores.