Ivan, that very much depends on the size of the GTs you're targeting. If you spend most of your GT time fishing for potentially very big fish, then by all means go for the heaviest rod. On the other hand, if you primary target are 15 to 20kg fish with the odd bigger fish thrown it, you may find you're better off with a PE8 rated rod like a Carpenter SP80M or perhaps something like a Keyolhu from Smith.
All of that said, I really do like the Komodo Dragon as it is flexible enough to fish PE8 comfortably and cast light lures but when you need it to, you can also really load it to the max. This will probably make Steve cringe but I regularly push the drag on my reels beyond 15kg (as measured by a Bouz which only goes to 15kg but which does have some error in it) and the Komodo is well capable of handling it.
Conversely, don't look down on the lighter PE8 rated rods. To give you some idea on what these rods can take, I had the drag on my Stella running at around 15kg on the SP80M last week and it is technically rated to about 10kg. Malcolm would have been pretty much the same as me on his PE8 rated TBL711.
For 10 - 12 kg, you're hardly even testing the KD.