There's some subtle differences in the trick system--SSX 3 will usually finish flips for you, for example, while Tricky leaves you upside down if that's where you stop holding the button. There's also a difference in timing with the jump button--you have to release earlier on Tricky. These threw me enough that I didn't get superboost on any of my three runs until I was almost to the subway section.
Still, I did get first on Merqury, so I don't completely suck. And my mental maps of the course are still great.