The WA (Write Acceleration) of the Lexar card would be useless to you, unless you're using the following cameras which support it:
1. All Kodak Professional cameras and pro camera backs, such as the DCS Pro Back 645, DCS Pro Back Plus, DCS 720x, DCS 760, DCS 760m and DCS 14n
2. Nikon D1x, D1h, D-100 (Requires camera firmware upgrade by Nikon. See Nikons web page for more details) and D2h
3. Sanyo DSC-MZ3
4. Sigma SD-9, Sigma SD10
5. Pentax *ist D
6. Olympus E1, Olympus C5060
So maybe the cheaper Sandisk Ultra 2 would be good enough. This being said, you might also want to consider Transcend CF cards. I've been using a 30x one since it came out, and no problems with it at all. A bit more expensive that the Sandisk Ultra 2 I think, but cheaper than the Lexar.