If you are actually going to do a decent amount of 4k gaming then you should definitely look into buying the AIB 1080 ti's. I know its going to sound scummy to say this but the blowers are completely inadequate for the new 1080 tis, regardless of whether they are specifically for FE or not, the blowers only stop your card from catching fire, they DO NOT provide an adequate cooling solution at all. One of my friends bought a gigabyte 1080 ti FE (with blower) and he says it runs up to like 80 celcius and he is not even running a modern game (world of warcraft) and NOT EVEN PLAYING ON 4K. The card hits a performance bottlneck at 82 celcius so if the blower is consistently running the card at 80 celcius with NO 4K GAMING, then this means that blowers are not even a cooling solution, they are a drop of water in a volcano. Also the blowers will heat up the rest of the system if you don't remove the panel to let the blower push the heat out.
There may have been a time where gpus where small and efficient enough for blowers to do something but that time is long gone. The new 1080 tis are massive beasts and every measure needs to be taken to provide adequate cooling for them, a blower just won't cut it anymore. Definitely look into getting either one of the following 1080 tis: ASUS STRIX OC, AORUS XTREME, ZOTAC AMP EXTREME. Since you said you are going to actually be playing in 4K i suggest you do a side by side comparison of the AORUS XTREME and the ZOTAC AMP EXTREME as they are higher clocked out of the box and can provide a little more room for overclocking. The sea hawk is also an option since it provides liquid cooling which is the best thing you can do for the 1080 tis (or any modern piece of hardware really) but I am reluctant to suggest the sea hawks because a few people on this same forum have had issues with massive coil whine from the sea hawks which leads me to believe its a common issue as opposed to just a few bad apples.
There are already a few people on this very website that have reviewed the 1080 ti ASUS strick OC, and the 1080 ti AORUS xtreme. If you end up choosing to get the 1080 ti ZOTAC AMP EXTREME just know that you might be waiting awhile because nobody in the west has gotten their hands on one for review yet.