Seems to me Type 1 CF are faster than Type 2. Type 1 refers to memory IC chip package whereas type 2 refers to those of harddisk type CF like micro-drive. DPreview speed check (write and read) on various CF cards on various digital camera shows that Sandisk Ultra 2 has the fastest performance. But this card is also the most expansive. Transcend are also good. The next one you can consider is the Higawara (spelling maybe wrong). :what:
1 last point to add. Harddisk type CF card performs like your ordinary harddisk. try not to drop it as there are delicate moveable parts inside. I read somewhere sometime ago that the type 1 uses less power than type 2. Someone maybe able to supply some evidence on this one.