I agree 1000% with Greg Fretwell. Surges can come in many different forms and paths. The best protection is to protect against all forms of surges.
Ideally, all the metallic services should enter the building together and be solidly grounded together at that entrance. With anything less, consider the point-of-use protector mandatory when more than one kind of service (power is one, cable is another) is connected. Even if you have the proper entrance protection and it is working effectively, the point-of-use protector is still a plus, especially if you have a transient heavy load device on the same circuit.
The ferrite bead is very useful to protect against common mode induced surges on signal lines. Years ago I had a stereo system which I had unplugged for a coming storm damaged by that storm anyway. It induced a surge in the speaker leads and destroyed the final transistors in the amplifier, as well as the tweeter coils in the speakers (about 40% of the coil wire was melted).
A ferrite bead is an inductive choke that fits around a signal cable. It can be effective against high frequency common mode surges, such as those induced by lightning nearby. They were usually on the video cable of a CRT monitor because the CRTs themselves could be a surge of surge that could damage a computer (by an arc in the HV section). They can be useful in general on all kinds of connections, though less so in shielded cables.
Stop as much as you can at the entrance. No means of protection can stop 100% in part because surges can be either differential mode, or common mode, or some combination of both. The ground bond in the panel will divert a lot of a surge to ground (the shorter and straighter the wire to the grounding electrode, the more surge energy that can be diverted). But you still end up with a combination mode surge. A surge protector that can work for phase wires helps even more.
Slow rise time surges (the most common) are easily protected against by just making sure that there are no voltage differences between metallic services. Fast rise time surges (less common, but can happen with close lightning strikes) can still cause damage even if reconciled by a point-of-use protector. That's where filtering becomes useful (premium power strips, for example). But there's even a limit to that because you can't use such filtering on the cable TV coax (fiber will help, but is best if it is all the way to the TV, which the providers of these services are not doing, yet).
