Go to the B&H Photo site, navigate to memory cards, then specify all brands, Compact Flash, 512 MB. Sort by price, low to high. Which brand it at the top? SanDisk. Try it with 256 MB, 1GB, or whatever, and SanDisk will always be at the top of the low-to-high price sort. Meaning: They're cheap. Now go to a membership warehouse. Which brand of cards do they carry? Costco sells only SanDisk. Meaning: They're intended for the mass market.
Digital Photo Review did a
comparison of CF cards. No matter how you sort the data -- by read performance, write performance, JPG saves, or RAW saves -- SanDisk 512 MB always comes in dead last.
You don't want to hear "Go buy Lexar," so I'll just point out that to me, it's worth spending a few more bucks for a card I can trust. I use Lexar. --Randy