The speed ratings for some of these memory cards have got me a little confused because manufacturers don't use the same standards and some reviewers quite often confuse mega bits with mega bytes per second. Lexar , for example, use 2000x and 1000x and SanDisk will use 250mb/s. Trying to work out the best card to get to eliminate buffer issues on a cost basis is a bit of a pain. Does anybody have any decent recommendations for both professional and non professional use for the XT2?