I was there on day 1 when the XL launched this year way back in March in Burgundy. I won't be getting this bundle because I already had an XL, and I had Mario Kart, so for me there is no point. However, there is a point for some, keep reading because the review starts now.
Back in 2004, the DS was launched. All was good. A smaller version called the DS lite was launched, all was better. Then the DSi with its internet connectivity, all was excellent. Now we have the XL, and things are about the same.
First of all, if you want a handheld game console to connect with the internet, take pictures to upload to Facebook or to have on your computer, and have access to DSiware games, then consider getting some form of the DSi. If you are content with just playing your games, stick with the original (the "phat") or the Lite.
To decide between a regular DSi and an XL model can be tricky. Both of them have pictochat, dsi camera, dsi sound, dsi shop, internet, and the function to play ds games. The XL advantage is big screens, 3 pre installed titles, and in the case of this particular bundle a Mario Kart game and decals to commemorate Mario's 25th birthday. All of these reasons are enough to not only get an XL, but to get this bundle in particular.
However, consider this. The XL's robust experience is fine for those of us with big hands, it is very unkind to those with small hands. It's like the Burger King commercial where it says that you need big hands to handle a Whopper, you need big hands to handle an XL.
If you have got a DS lite, or no DS at all, and want to upgrade to an Xl and you still don't have Mario Kart DS, this is a bundle to get.