Dagger bills this boat as a river runner; however, you have to take that designation with a grain of salt. It may be more river-worthy than a low volume playboat, but it's still a short, planing hull boat, which translates to a lot of work getting from point A to point B. The GT also requires a fair bit of effort to keep it on line. For example, ferrying across a fast moving stretch of flatwater requires numerous forward and correction strokes to avoid losing ground. In an older style boat, this would have been a "no effort" move--set the angle, take a stroke, and let the river do the work. In general, I would say that it took probably 3 or 4 strokes in the GT for every one I would have needed in an RPM when doing the basic moves of running a rapid. When Dagger gives the GT a 5 out of 5 for hull speed, I would guess they are comparing it only to other flat hulled boats. It sure isn't fast in my book!
Of course, this style of boat also has its benefits. The GT carves into eddies quickly and precisely. It front and side surfs easily, and it's very forgiving of too much angle when starting a ferry. The boat presents more resistance to rolling than a displacement hull boat, but it's quite easy compared to something like an Id or even a Booster.
If your tastes lean toward hole surfing and playing, then this would be a nice beginner boat. If you like running the river between playspots as much or more than the actual playing, go with something with more hull speed like an RPM.