Mario Kart is one great series, the new one on the Cube is an awesome game, and the one on the GBA, that features all the tracks from the SNES Mario Kart as unlockables is awesome too.
In the case of games that you can't still buy, I am all for it, I have stacks of them myself, but you said to go download them INSTEAD of getting a GBASP, so you are either avoiding the games you can still get on the GBASP and missing out on them, or you are downloading them when you could be buying them!