Figure 8 style belay devices, in general, are heavier and bulkier than tube style devices. They are used primarily by military or Search and Rescue for rappelling.
As far as figure 8 style devices go, the BD Super 8 is an excellent product.
As with any figure 8 device, it does not dissipate heat very effectively. But it is a tough device, and offers smoothe rappelling.
But, I prefer tube style devices. While using any figure 8 has, there is always a slim chance that the rope may lock up in a cat's paw knot. Figure 8 devices also tend to twist the rope more than tube style devices.

Similar Products Used:

Black Diamond ATC