I don't like the sandforce compression crap. It's smart, but it kills performance if you need to read/write incompressible data (IE compressed RARs). All current benches on them are misleading because 99% of them are done with highly compressible data (IE OS files or synthetic bench data).

Anandtech has an article up a while ago where they used an incompressible data file for IOmeter and the results were UGLY. The lack of a buffer really shows.