They dont fit modern GPUs
it worked when all they had to do was cool the GPU die itself, but the VRM's and VRAM need the full cooling performance now too (let alone cards with VRAM on the back of the PCB) so they're not compatible.
Even simple changes like variants moving the VRMs to the left or right of the GPU caused headaches because they'd hit the retention brackets on heatsinks for the other components
I've still got my G12 here, but until i find a free/dirt cheap asetek unit it's not worth the price to cool a GTX 1080 (the most powerful GPU i have that fits it)
The EVGA CL24 AIO has the legacy Asetek waterblock head with the bayonet mount that the NXZT Kraken G12 needs. I have no idea about pricing in Australia, that's up to you to decide.
I used this kludge (CL24 + G12) for an RTX 2070 Super Founders Edition and swapped the NZXT fan with a Noctua one.
As you mentioned, there are compatibility issues. I had to clip the ends of the AIO waterblock cowling accommodate for the bracket screws or some such nonsense, voiding the warranty. The single fan EVGA CL12 AIO had a different cowling and worked without modification but naturally it didn't have the same thermal performance. This 240mm AIO was never on NZXT's list of recommended parts but it did work fine with the unsanctioned modification.
Amusingly, the G12 mod makes the GPU bulkier, turning it from a sleek 2-slot card to something like 3.5 slots because of the size of the Asetek waterblock head. It also qualified it for the Ghetto Mods discussion thread.
Eventually I acquired an Alphacool waterblock for the GPU which had great thermal performance (it was pricey though, not a great value). The EVGA 240mm AIO is now cooling the CPU on my daily driver Windows PC in a normal usage and the G12 bracket went to the e-waste recycling heaven. The 2070 Super FE is now back with the factory cooler (and its noisy fans) and I have a fine Alphacool paper weight shaped like a 2070 GPU.
It was a fun adventure that led to my first custom cooling loop. Not something I'd replicate but some lessons learned, both good and bad.