^How was the brake dust on the Stoptech pads? As bitey as OEM?
I wouldn't expect the Project Mu NS400's to be magic. With brake pads, nothing really comes for free. You always sacrifice a bit of something, to gain elsewhere. I'd bet the StopTech pads emit more brake dust than the NS400's.
Next time round, if I could find something more bitey, but still emits less brake dust than OEM, I'd give it a go.