It depends on the quality of the surge suppressor. The important details on a quality device are covered here:
Most people don't take the time to understand the ratings for clamping voltage, joules suppression, and response time... and the $9.99 surge suppressor generally isn't much better than a power-strip but people can't understand paying $70 for the quality one.
The best ones usually have some sort of insurance policy-like guarantee against equipment damage, as well. *AND* they need to be replaced periodically because they're taking the hit so your devices won't.
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