I cant speak to ceramics. Metallics have better stopping "power" but wear down rotors faster. Composites (I am guessing organics) dont have as much stopping power, but spare the rotors.
Composite are a softer material and wear down faster, but they tend to stop smoother due to the soft material. They also have less black dust build-up due to the organic material.
Semi-metalic have metal inpregnated into a carbon material. They last longer and stop great. The carbon material causes the excessive dust build-up.
Ceramic last the longest. If you have a problem with brakes wearing down to fast, these are the way to go. The downside is cost. These brakes cost about 2-3 times more the semi-metalics.
I've heard about a titanium pads for extreme duty and racing. These make the ceramics look cheap. Other than that I've not heard any more info of them.
So composite would be the best choice if I'm concerned with warping the rotors? On the web sites I'm looking to buy from seems like metallic and ceramic meet OEM and composite are "performance."
I do a little Road Racing (only 2 events a year) but mostly just Street Cruisin. I use the Porterfeild R4-S Brake Pads.
They take the heat better than stock pads, are easier on your Rotors (which are expensive) and are quieter. They work like stock pads when cold, so perfect for the street.
I have had these pads on for over 1 year with no signs of wear yet. They have 1 Track event on them and about 3,000 cruisin miles, so too early to tell how long they will last, but I figure if I get better braking performance it's still worth putting new ones on every 3-4 years.
I think they say they are made from "Ferro Carbon" on the box.
Only downside is they are a bit more money and there's a little more Brake dust, but I wash the car once a week anyway, so no big deal.
They are available at www.muggziperformance.com
For a daily driver the composite pads are probably the best choice. Composites are the closest to OEM. Some of the newer cars came out with semi-metalics as OE, but most older vehicles were composite. Ceramic is starting to get into "performance" parts. The main thing is what are you looking for in your application, and how much do you want to spend?