I don't have a lot of time on that hull so take this with a grain of salt.
I have ridden a friends GTR, same hull as the new GTI, and I found the trim does not make as much of a difference as it did on a 97 GSI or an 04 RXP. When using the trim on the older models I found it made a big difference on how the ski handled chop and how it handled when carving corners when jumping waves on the RXP with full nose up trim you had to be careful as it really launched you nose up. Riding the GTR the trim does work and you can feel a difference just not as noticeable as on the older skis. My .02 YMMV.
What I do like on the newer skis is the IBR system once you get a few hours use the two fingered control when manoeuvering at slow speeds is fantastic.