The fronts (7581.95.08.92) aren't a perfect replacement. The shape is close enough that I was able to use them after a tiny bit of grinding to clear the sliding half of the caliper and I had to bend the spring clip to put enough pressure on the pads to hold them against the caliper.
Without riding back to back in comparison to the stock Nissin pads, especially when weeks lapse between rides, I'm not expertly sure how the PFC pads compare. I'm certain that they do need a little heat to work, were stronger when slowing from higher speeds and have good feel and predictability. They do drag more than the stock pads and make a pleasing (at least to me) buzzing/whistling (whizzing?) noise when on the brakes that was unfortunately a little distracting off the brakes when it would take a second or two to become inaudible because of the drag.
A coast race on the San Jose side of Mt Hamilton, had me probably a 1/2 mile behind everyone else by the end mostly due to the drag.
I know from experience that the PFC pads will be very easy on the rotor.
I love Performance Friction's Carbon Metallic brake pads on other bikes that I've used them on and will keep using my current set until they wear out but can't recommend them for an '06 DRZ400SM because of the fitment and presumably at least partially related drag issues.