Can't find matching DDR2

[Gti]

i have 2x1 OCZ pc6400 4-4-4-15 Gold edition.
I can't seem to track down another pair so i was wondering if getting say, crucial 2x1 5-5-5-18 would be ok? then the OCZ would adjust to the slower timings?

 

[Gti]

Thanks, i've read around and still don't have a definite answer on how using 4 sticks of ram instead of 2 will affect the OC on my e6600 (2.4 to 3.0). Is it likely to?

 

[Gti]

Thanks, after looking around i can get new ram straight from corsair for the same price they go for second hand. Not to mention the sellers of second hand ones I've messaged can't provide proof of purchase to make a claim if i need to.

This one on OC looks promising http://www.overclockers.co.uk/showproduct.php?prodid=MY-135-CR&groupid=701&catid=8&subcat=144