I've used both for years.  For the most part, Spybot just catches certain notorious tracking cookies, but occasionally it comes upon something that poses an actual threat that Norton has missed.

If Spybot slows your computer down, don't have it load at startup, just have it do a scan overnight or when you're otherwise away from your computer for an hour or two.  

I've not noticed any speed reduction when it's running in the background, but I also don't recall it ever catching anything when running in the background--just when it's doing a scan.  

On the other hand, when it's doing a scan, I have noticed it slows some computers down a bit, especially older ones.

TLC
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--- On Fri, 9/7/12, Dean Kukral <[log in to unmask]> wrote:

I use Norton Internet Security.  I also use Spybot Search and Destroy.

Is Spybot redundant?  Does it just slow things down? 

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