I believe so, I think they've done all the docs we've seen (Sonic, Virtua Fighter, JSR).
As for the Combo race, it's tough, but after the fifth time trying I remembered that it is way easier than you think. Since Beat waits for you to catch up in the drain pipe, the race really starts halfway through. I just skate and jump, trying to pass Beat but also avoiding him so he doesn't bump into me. If I get past him, I just need to nail the jump up to the steps and take the path down the hill to the right (Beat goes left). Even if Beat gets past you up the stairs, you still can beat him to the tag if you take the street to the right.
It just sucks that the Combo race comes right after the Yoyo race. Two of the hardest races are one after another. Don't think the JP version is like that though, I think Combo and Yoyo have completely different challenges. Or at the very least, Combo's is different.