Material does not really matter. What is important is the friction code On the edge of the pad there will be a friction code printed, usually two letters, as in FF. First letter is cold friction, second is hot friction. The higher the letter, the more agressive the brake pad is.
You should also bed your brakes in for top performance http://www.zeckhausen.com/bedding_in_brakes.htm
This can make a huge difference, particularly with high performance brakes, but should be done with all brakes.