Was pull 001 the strongest of the first three pulls ?
Most dyno operators use the lowest of the before runs and the highest of the after runs, this is not a problem as long as the first run was not way down on power.
Do you have a run to show power with the RexXer flash before you tuned with the PCV ?
Out of interest why didn't they use the RexXer to do all the tuning.
I don't know what would be gained by comparing the Akra, AR, Termi without any tuning.
The one that is closest to the standard pipe would work the best with the standard tune.
I would expect the Akrapovic to perform poorly with the standard tune.
The more that the pipe changes the character of the bike (better or worse) the greater the need for tuning.