SRB2Kart v1.3 is one of the best racing games I've ever played. Granted, I'm not a connoisseur of the genre, but I've played some Mario Karts in my time, and Nintendo does a good job there, but SRB2Kart is just incredible. It has a ridiculously high skill ceiling, which on one hand, can make it a bit harder to find people of an equal skill level, and harder to get newbie friends into the game, but on the other hand, learning the ins and outs of the game and getting good enough to get most of the Record Attack medals is incredibly rewarding. Even with the single-player content being largely unfinished with the exception of Record Attack, there's still an incredible amount of fun to be had. Also the item design is a very big part of why I think I enjoy this so much more than other kart racers that I've played. The SPB, or Super Propelled Bomb, doesn't just go to 1st place and beat them to death like a Blue Shell might, it just chases after them at the same speed, meaning 1st has to play perfectly, or else lose a big lead on the other racers, making frontrunning more about skill under pressure, in 1st place, or in 2nd place and back, about good use of items to trip them up, and strategizing whether to fight the other opponents behind you or to fight those in front. Jaws is a bit more interesting than a Red Shell, because instead of following the track, it locks onto a target and goes towards their back at all times. This can allow you to trick the Jaws into destroying itself, if you can quickly turn around a wall faster than Jaws can get past it. And my favorite, the Eggman Box doesn't just spin you out for a second, it gives you a countdown until you explode. You can mash the item button to make this go off faster; so if you're annoyed that you hit it in the first place, you can try to surround yourself with other people to drag them down with you. Almost all the items are designed like this; my only complaints with them is that Shrink and Grow kind of serve the same purpose, just in different ways, and Grow stays in your item box while it's in use, which isn't great when you're too far to catch up and squish someone to create extra distance for yourself. Of course, you can cancel it which works too, but that's hard to remember. Either way, I'm not too broken up about this because I've heard it's being fixed in V2 anyway.
The other great thing about SRB2Kart is the incredible community support. If my memory is correct and I counted right, at least half of the characters from Super Smash Bros. Ultimate at this point have been modded into the game at this point, along with dozens of other characters you'd never in a million years expect from an official SEGA or Nintendo product. It's become sort of a racer MUGEN at this point, and it's beautiful. Overall, the great game design and the community mod support come together to create a truly magical experience.