If you want it only to play GBA games, get the SP.

I think the DS Lite is the better buy at this point.

For portability purposes, the SP is the greatest handheld ever. It also plays GBA and GB games and handles very well with the controls.

DS Lite; how is this even a question?

DS Lite. The GBASP is too thin which cramps the hands when we're talking about a game like Metroid. Plus that way you can try Hunters (maybe) or just play other DS games too.

Depends on if you have an 3DS or not.

Have a 3DS - Go with the AGS 101 SP with the brighter screen to gain access to GB, GBC and GBA games.

Don't have 3DS - Go with the DS Lite to gain the GBA and DS library.

SP is a damn near perfect device.

I agree with the DS. There's no point really getting a GBA at this point. Even if it is the SP.

Honestly, I'd recommend you get an original DS phat. so the GBA game isn't hanging out the front of the system. I've had many times with my Lite that I nudged the GBA cart a bit and the game froze. The DS phat or the GBA SP are the best ways to play GBA games imo.

Gba sp, best d pad and clicky buttons, backlit, more portable, best choice.