What i see is advertized durations don't match reality well. A cam with a lash setting of .028 and a 1.5 rocker will have different amount of true duration at the valve versus a cam with a 1.7 rocker and .019 lash. Then add in the intensity of the lobe design, and the difference becomes greater yet. I have two cams with supposedly similar specs, bud the differences i showed above. One cam used a 1.5 rocker and big lash, the other an inverted flank cut lobe, tight lash, and 1.7 rocker ratio. The tight lash cam with 1.7 rockers gave better average hp installed at 108, rather than 110, the recommended install.