For those that are interested here is a comparison of the GBA SP 101 that was launched in 2006ish. It comes with a 2 level backlit screen as opposed to the poor on or off front lit screen of the 001.
So, here is are both machines set to low level light, in the 001 case, light off.
Here is the 001 light on and the 101 light on low. Difference is already massive.
Now both consoles set to bright.
Now showing Mario Kart on the 001 with light on.
Now on the 101 with light on low.
And finally light on high.
As you can see the 101 is so much better than the 001. The screen is wonderfully vivid in person. Any serious GBA fan should own one as it is the perfect machine. Plays both GBA and GB games in wonderful vivid colour.
Note I had to move the camera away for the Mario Kart bright shot as it just came out as a blurry mess.
I have one of these myself, a fantastic unit. I remember when the SP came out the jump from the original was huge, hard to believe it was the same game. But with the 101 the difference is even greater, better than a micro!
Night and day. I swear by mine, the 001 hasn't been used once since the 101 came along. I'd still like to kit out my original GBA with an Afterburner, though- or better yet, swap the 101's screen and pop it into the original's case.