I bought the original GameBoy Advance a month before the SP came out. The SP looks great with the backlit screen... but the original one is very hard to use since the screen is so dark, and then when you try to get under a light to see it, the shiny, glass-like screen reflects all the light and you still can't see it. The SP is probably better, but it's obvious Nintendo knew this was a problem with the original GBA before they released it... they should have never released it while there were still problems with it.
The only reason I gave it 2 stars instead of one was because the graphics are pretty good and the game cartridges are small... but those are really the only redeeming qualities about this thing.
It also causes cramps for anybody whose hands are bigger than a 5-year-olds.
The games are way too expensive too! (about the same price as PS2 or XBOX games)
Overall... it's just not worth the money.