Well I've spent a LOT of time with this game now, and have given it time to mull over in my head.
A 6/10:
Basically it has fun moments, but there was too much loss compared to other GTA games:
1. Car handling is really inconsistent in this game vs. 3D GTA titles. In 3D GTA titles, the quality is much more even and predictable. In this GTA, there are some downright atrocious-to-handle vehicles.
2. Music, while obviously having to fit for cartridge consumption, loses so, so goddamn much. One of the best things about GTA games is radio stations and radio station personalities, but all of that is dropped here for purely instrument tracks. It HAD to be dropped for space reasons, but the loss is felt deeply.
3. Visuals. Not much needs be said here.
4. This will obviously be the controversial segment of the post. Fucking touchscreen gimmicks. Now I went through a period after DS launch where I liked these bizarre touchscreen gimmicks because it was new, but that faded quickly and it turned to distraction to terrible when used incorrectly. Here in my opinion is where it is used very, very incorrectly. In countless scenarios, the game decides to break up good fun action with lame, skill-less touch screen mini-games. Unscrew this, cut this, scratch that. Even after they introduce the elements, forever you go into the game you will occasionally encounter these dumb things that stop the flow of the action and ruin pacing. I don't want your touchscreen molotov making, stop it!
Cutting drugs out may be neat ONE time, but is boring and fun after the 5th time. It doesn't add immersion, it doesn't add challenge. It adds boring. It stops action.
In GTA games, I don't want to fucking stop to unlock ignition just to hijack some cars. I don't want to screw wires into a bomb. I don't want to revive dying heart patients. It's not even particularly good CONTROL, since constantly having to move from controls to stylus is cumbersome and annoying. About a billion times I wished there was an option to turn it off and play it straight. I would enjoy the game more this way, since there is a pretty solid foundation beneath.
5. Obvious limitation of DS, cannot be helped, but controlling vehicles via D-pad is never preferable, so it is a loss vs. other GTA games and it is less fun driving because of this.
On the PLUS side:
+ I really like drug trafficing
+ I really like the way you throw things, like the boxes off the back of your truck and the molotovs. Very elegant way of adding precision to the top down GTA titles.
+ Missions have very good variety and are fun when you get past the flaws listed above.
+ Great humour and funny dialogue. Very cheesy but honestly very enjoyable to watch.