I believe that you'll want to check out the specs on each surge suppressor. Based on what I read in my brief search this morning, the joule rating has to do with how long a surge at a certain load it can withstand (so a 600J power strip with a connected load of 1200W would withstand a half-second surge). As an example of the response time, the specs page for the MAX5100 that I use includes the following:

Response Time <1ns

Also, something to keep in mind is the difference between max rated load and real-world load. 1800W is the maximum that can be provided by a single 15A residential receptacle circuit, if I remember correctly, so if the 755 ran at a constant 1800W it would require its own dedicated circuit just to keep from tripping the breaker. In reality, the load will be significantly lower than that.

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