Will there be a noticeable difference between CAS latency performance?

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I currently have 8Gb of G Skill Sniper 1866 RAM(Cas latency 9) with two modules.  Usually my RAM is full so some programs are relying on SWAP to run correctly so I want to upgrade to 16Gb.  I also have one 8 Gb module of the G Skill Ripjaw X series 1866 with A CAS latency of 10 in another system that I could switch out and use.  If I have the 1866 CAS 10 will it be noticeably slower than if it was CAS 9?  The Sniper series is almost $20 more than the Ripjaw X for a CAS latency of 9 instead of 10.  

 

The 16GB of CAS latency 9 would be quad channel, where the CAS latency of 10 would be dual channel.  I've heard that dual channel is generally better, is that true?  Which one would probably yield better performance?  I usually have lot open such as video editing and programming plus about 30 small programs such as documents and stuff like that.  I do game but that is not the emphasis.  

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Last I checked, the 8350 didn't support quad channel memory. You may have 4 sticks, but it is dual channel.

Most likely, no, the performance difference wouldn't be huge, but I always go for as low of a CL as possible.

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I didn't realize I couldn't have quad channel.  I read somewhere that if you use two sticks in the same channel the memory controller will slow the timings.  Is there any truth to that?