The two modes of operation are nice, for movement and simple servo movements I used the SSC Mode. For complicated movements of my Hexapod and Robot Arm, the group move made the motion very smooth.
Since all of my usage of this controller was done via Java I actually created a class that allowed use of this controller. It's called the LM32 and can be downloaded with the source from the book. I also created two interfaces implemtned by the LM32 called the GroupMoveProtocol and the SSCProtocol. So for robots or arms you can use whatever protocol makes the most sense for you.
I can't really say anything bad about this controller, though sometimes I feel like it's being wasted by just using 8 servos. I guess I need to buy more servos.
You can get all the details about the LM32 from the Lynxmotion Site.
You can get a Mini-SSC II but it cost more, has 24 less ports, it does not implement the "group move" and power is more difficult to connect.
I would recommend this unless space is an issue it's size is 3" x 2.3".