Memory Stick Compatibility Question...

[mkim1120]

I recently purchased a Sony Cybershot DSC N1 for my girlfriend, but now need to find a memory stick.
From my research I know that the Sony - 256MB Memory Stick PRO Duo Media - High-Speed (MSX-M256N) off of wolfcamera.com, but I also have seen a 256MB Memory Stick PRO Duo Media - High-Speed (MSXM-M256N).
Is there a difference between a MSX and a MSXM?
Can someone please clarify this?
And are there any better choices out there other than the Sony ones?
The reason Im choosing the Sony High Speed is because from my readings that this memory sticks allows faster uploads. Is this true?
Thanks in advance!:confused: :confused:

[TampaJim]

I don't know the difference between those two, but I do know that you don't have to use Sony branded memory. Costco has Lexar Professional Memory Stick Pro 80X in the 1GB size on sale for $69.99. The Lexar Pro series carries a lifetime warranty as well. Just a thought.