GT's are notorious for high spine spikes at one side. In addition they often are not terribly well matched within a dozen from shaft to shaft or dozen to dozen. For my compound use, I gave up on them along time ago because of this. However, I will start off with some in my new longbow simply because I'm not good enough (yet!) to worry about the imprecision. You can usually get the "flyers" to pull into a group by turning the nock to a different fletch. It can definitely take some experimentation. If you do not have access to spine testing equipment I would recommend buying Goldtips from someone like Jerry #@ SouthShore Archery, who tests each shaft, finds the high spine side and marks it on the shaft for you. he does not match them per-se, however it's much easier to nock tune them this way.
CX shafts in general have a far better Spine around shaft reading with little high/weak variation, and are more tightly matched from arrow to arrow, dozen to dozen.
The real benefit that GT has over the CX Heritage is that GT uses a 100 pure carbon fiber, and will retain straightness over time/abuse longer than a composite shafting like CX Heritage, and any of the Easton or Beman (or 3Rivers "trad only") shafts which can and will bend/take a permanent set at some point.
CX's other shafting (Maximas, Piledrivers, Mayhems, etc) utilize a pure carbon makeup, unfortunately they do not offer the weaker spines in those shafts and/or they are often too light for most traditional shooters.