I've been trying out Vista Cube 2.0. It's got a bit of an initial delay too, but it's nowhere near as bad as what I saw with iCube. I'm starting to like the look of the Vista cube and Spunk3's cube, but I really was a big fan of the iCube as well.
It might be possible to port the look of the iCube onto the Vista Cube 2 or S3 cube framework. I don't know if that would make the problem go away. I haven't decided yet if I'm going to take the time to try this myself.
The only downside of doing that (and it's a downside for the Vista Cube and S3 cubes as well) is that the customizer thisguyinoc wrote works with the iCube. The S3 customizer (which also works for Vista Cube 2) isn't quite as user friendly, but it does get the job done. I assume that by porting the iCube to the Vista Cube 2/S3 cube framework, it'd no longer work with thisguyinoc's customizer.