The Gigabyte GTX 1080 Ti Aorus Xtreme ($750) is one of the largest cards weve looked at, particularly in the cooler department. The VRM setup is similar to the Strix with regard to power capabilities, but still runs into similar OC limitations as the Gaming X. These cards are already near their maximum clock, and pushing higher begins threatening frametime stability in ways that may sometimes force toggling the OC for certain games.
The Gaming X ($750) is roughly 3% faster out of box than the Aorus Xtreme, but overclocking allows that to more or less equalize. That said, its not necessarily worth overclocking the 1080 Ti cards given how close the voltage and power constraints are.
Looking at thermals, the two cards are also similar; Gigabyte runs a bit warmer on the FETs, but also uses a different power design. GPU diode temperature isnt too dissimilar, noise output is effectively identical at 50% speeds, and performance overall is within a few percentage points.
Price is also the same as the Gaming X. If you want cards that do well out of box and never want to overclock an FE card, then these are fine considerations that can grant 6-11% performance uplift over the reference cards. If you remove the thermal constraint, that advantage is closer to 1-3% over FE.
It comes down to picking the card that best fits the build, both physically and aesthetically.