Dual Titan RTX Machine Learning System - Air Cooled vs Water Cooled - Anyone have experience with 2 Cards in a system?

I’m not sure where to post this so here it goes… I’ve got a build list going for a 2x Titan RTX machine learning system.
From what I read the cards hit thermal throttling in air cooled systems that are working on algorithms that take a day+.
We have such a need for this extended training.

This is the build I have going: https://pcpartpicker.com/list/WqN9Mc I was going to settle on liquid cooled, but I can find waterblocks for the Titan RTX cards. Does any one have a 2x Titan RTX Build that is air cooled and if so what case do you use and have you been hitting the thermal throttling.