As an alternative, might you consider an iPod touch?
We have a "family ds" that the kids used to fight over. This year 2 of them got iPods for Christmas. Now the DS sits unused...
Games on the iPod are often free or $1. How much are your DS games? Lemme tell you , I feel like a chump. I paid $14.99 for Deal or No Deal on a ds, but was able to get a version of it free on an iPod. I wouldn't dare spend $10 on an iPod app, but I used to spend $20 on a ds game like it was normal.
And there's no pen to lose!!!!
Yes, I understand, the equipment wouldn't be cheaper, but the games would more than make up for it!
Just an alternative thought to consider... Take it or leave it.