Well guys, I think I tend to agree with you. I've only once seen a bow shoot faster. This was 360fps. But this was at another shop and was the owner's bow. And he was shooting and arrow WAY too light for the set up. But he shot one pin out to 40 yds. Shooting an arrow with a lighted nock it was like a laser.
As for the shoulder, its not muscle but a nerve issue. And 70# is really no problem for me. I've been shooting bows for a long long time and my back muscles are conditioned. In my prime, I have shot a bows with DW of 110#. Just because the shop owner said I couldn't do it. Five shots only and that was enough. Anyway, I just don't want to go crazy until everything gets fixed. I have a Cheetah set at 51# that is a dream to shoot. Quick, quiet and accurate.
I appreciate the comments and I am also suspect of the speed.
I would have to say that the chrono needs calibration. But I would say that it is definately over 300 fps.