I am not sure I will find custom water loops for my CPU or cards at my place.
I had bought a gigabyte server motherboard for my current system because it had a custom cool loop. Never found anyone in the city who could provide the coolant at my geographical location. But If I am spending so much money I might look for branded options if available at that time.
A Quadro 8000 (NVIDIA Quadro RTX 8000) or 3090 ti, I will choose when I am ready to buy the system. Quadro does have double VRAM.
Thanks