"Strix" and "FTW" are ASUS and EVGA's higher end cards respectively.
They're binned better than some other options they have.
The Strix is a base of 1.61 and boost of 1.73GHz, with the FTW base 1.72 and 1.86GHz boost.
On that alone, the FTW is "faster"..... but in real world performance, I wouldn't expect many substantial FPS gains.
Availability is limited on some of those cards..... and you're looking at $600-$650 range for them currently.
Considering that, another (potential) option for consideration would be a 1080TI FE which is $700 and can actually be purchased at that MSRP.
While it's a reference design and will likely run a little warmer, it's a stronger card overall.
https://www.nvidia.com/en-us/geforce/products/10series/geforce-store/