Mario Kart Wii takes the crown for this one, partly because every map stops being a nerve-crusher at some point. However, this game loses this category for it's inclusion of the Super Monkey Ball Stages, because these tracks are picky and require you to do things that can cost you the race just to make it to the end.
Again, this one goes to Mario because since they use the Weight system, in which the cars you use differ based off the size of the character itself. This makes it balanced without losing variety. Sonic, however, could've won if he had just let us either pick the same character or let us pick the vehicle we want even if someone else picked the character already.
Sonic slowly recovers this fight because at least in his game, the power-ups aren't game-altering. Therefore, I can focus my attention to more important matters, which leaves...
Clearly Sonic wins this one because in Mario it's absolutely useless. I finished Mario Kart Wii and almost never used Manual drifting. Sorry...
Sonic has better music, Mario has the Blue Falcon for a Kart, and-- Ooh look: a puppy!
Well, it's a draw. Well, nuts. And here I was, dancing around, ready to hand the Blue Blur his sparkly trophy, but noooooo, I had to get distracted by the Puppy RIGHT AFTER COMPLIMENTING MARIO. RAAAAAAAAAAG--!
Well, in the end, you have a choice: Either play easy mode then never bother with it for a long time, or beat the full game before giving up but not without getting worked up over a video game. Which game's which? Well, here's a hint: the former game I insulted doesn't have Blue Shells in it.