I have to agree w/ Matt/Tn. , something is off w/ the chrono.
A GTO BC 60/28/300 is 324fps. and 70/28/350 is also 324fps. It's IBO rating is 340-350 @ 30".
The GTO may have been an earlier produced model that had a bad batch of string/cables. They were not pre-stretched properly. So no one was getting IBO or even close.

The 06 Ally I had for a short time had a BC of 70/29/350 at 319fps.

Something is wrong somewhere.