CF speeds in S400

Hi, when I bought my S400, I bought a regular 256MB CF card with it. I could have paid a little more and got a 12X lexar card but someone told me that the S400 only has write speeds of up to 4X.
Is this true? Can you guys confirm this for me? I'd like to know if I should switch up. Thanks.

I'm not sure about the camera speeds. THe CF review in DPreview shows all cameras are below 4x, even the better profesional cameras are the same way.

With a faster CF full card downloads are that much quicker when used through a CF reader. Also, the CF card could pull double duty as thumb drive. To transfer files between computers.