DS or PSP?

[Rostum]

And how much do Game Boy Advances actually cost now, either brand new or second hand? In the UK you can get a brand new Game Boy Micro for about £30 or a GBA SP for £20 if you look around. Cheaper then most DS Games. Hardly costing a fortune.

I've seen GBA SP and Micro's for $100AUD. The DS costs $180AUD. I'd rather get a DS than buy both a DS and a GBA. =\ Even if they are as cheap as you say, you're still saving, unless you really don't want the DS side of things.

Edit:
I don't know why you wouldn't want the DS side of things, if you like the GBA games a lot to buy one, you're going to love a lot of the DS games.