In our testing we found Orbit performed quite well. Quick and responsive. It would however be nice if the Home button returned you to the page you activated Orbit from.
Another great feature would be the launch of Orbit using a pinch gesture on the Springboard. Turns out Steven is already working on this and it may be including in version 2 of the app.
Take a look at the video below to see pinch in action. You can purchase Orbit for $1.99 from the Cydia Store.