Look past the flaws, and the DS version of SEGA's crossover racer is another great racer to have in your DS collection.
As for the racing itself, it's actually quite crazy, sometimes crazier than any Mario Kart game. Whether you play a character that rides a car, a hover vehicle, or a bike, you'll have a well controlled racing experience on your hands. Even with the use of "gimmicks", which are pretty much SEGA's take on items in other kart racers like Mario Kart and Crash Team Racing, with the red missiles being similar to red koopa shells, a remote controlled rocket being the near equivalent to the blue koopa shell with the only difference being that you can set it off anytime, a barrier to temporarily protect you which was seen in Crash's racer, and even Star Power. What Star Power does is that depending on the character, they'll either gain a massive boost of speed, or by slowing their foes down by playing music. These only work when you're behind the top three however as if you use it when you're in the top three, you just throw the star, though it does make the game feel a bit more balanced that way.
Let's move on to graphics: for a DS version of a game that's on multiple consoles that OBVIOUSLY have more power, this version actually still holds it's own quite well on a more limited handheld. The vehicles and characters look very good. The environments look great, and a nice color palette to back it all up. What's also very neat is that the framerate is still very smooth for a DS game.
Next up are the controls: though unlike the console versions where you use an analog stick (unless you play this on a 3DS where the analog nub works on D-Pad controlled games, but as I don't have a 3DS yet, I can't comment on that), you can only use the D-Pad to move as you're accelerating. Luckily, the controls work great enough with the right response time and it feels just as good as Mario Kart DS, so no problems there.
A few other things to comment on and I'll start with the stage variety. Like I said, I comment the developers for adding such variety in the character roster, but while most of these tracks are a lot of fun to race through and look really nice on the DS, they could be a little more varied in what franchises to represent. The biggest culprit in the franchise section is the Sonic series. I know Sonic is a major franchise for SEGA, but why does that series have nine courses while the few other courses to be referenced (Billy Hatcher, Jet Set Radio, Samba De Amigo, and Super Monkey Ball) only have three each? Why weren't there tracks dedicated to Virtua Fighter, Alex Kidd, or Space Channel 5?
Now onto some of the gameplay modes, other than your regular grand prix and time attack modes, there is also a mission mode. The missions mainly consist of battling other racers, getting a certain number of some objects, drifting a certain number of times, avoiding certain objects, driving through the right colors of giant rings, and of course, racing some adversaries. Most are quite fun, but one mission in particular has an unclear objective where it only states that you have to dodge one thing, but when you play it, you have to dodge another obstacle that will also take away your points without telling you. Luckily, it was only one mission so it's nothing too major.
You'll also get an achievement mode, but personally, I never really cared too much for them. Not that they are a bad thing, it's just that I don't like paying too much attention to them and rather focus on unlocking more useful things like more characters.
One thing I have to criticize in regards to a bit of the replay value is that you have to BUY background music in order to hear them in the game. Hearing the same music over and over again gets a bit repetitive and extra music tracks help prevent it from being such, but we have to buy the other ones? We didn't have to do that for other things like racecourses as you'll race through the unlockable ones anyway, as well as the characters because you'll race them anyway, why not do the same for the music?
But speaking of music, the DS version of the game uses mostly MIDI versions of the soundtracks, but they are very well done and some of the worst tracks they could put on there (like Sonic R's Can You Feel the Sunshine and Super Sonic Racing) are actually more tolerable. I think my most favorite track in the game has to be The Concept of Love from the Jet Set series (though granted, I've yet to play a Jet Set game) mainly because it's the catchiest in the game and suits the Tokyo based stages very well.
Lastly the multiplayer, now granted, I have never played the online portion of it (due to my DS not being compatible with the online service I have), but in local download only multiplayer, players who don't have the game have the option to play only a few characters, but only with the first player picking the characters and the tracks. Luckily, the game runs very smooth when you have full bars, but every time a race finishes, you have to turn off the dang systems every time, which is annoying if you want multiple rounds.
But once you get past those flaws, Sonic and SEGA All-Stars Racing is still a great racing game to have in your DS collection thanks to its widely varied roster, still very well done racetracks and fun local multiplayer, though if download play didn't have you reset the system after every race, it would have been a little bit better and if more franchises got referenced in the stages it would make the variety in the game stick out a little bit more.