I don't know the answer for me and I certainly don't know the answer for you, but I'll give you a few thoughts.
I decided that the extended holiday return period was a good chance to find out the only way that really tells you anything - buy one. I looked at my 7, a 128GB phone with only about 40GB used, and decided I could make do with a 64GB X. That was worth about $200 right there...but I digress.
The hardware itself is gorgeous. You really have to live with it a bit (and maybe look at the iFixit teardown) to appreciate what a tour de force this phone is.
Software/UI/UX is another issue.
Everything takes more motions and more time.
Unlock with TouchID? Just press (or now double press) the Home button. Unlock with FaceID means tapping the screen or the side key, then arranging the phone so it's looking at me, then swiping up. [I do not have rise to wake enabled, never have and don't plan to.]
ApplePay? With TouchID I just grabbed the phone from my pocket with my thumb on the Home button and jabbed the phone at the reader - done. With FaceID I have to double click the side button, then look at the phone at an angle that it can register my face, then confirm that it registered my face, and only then can I hold the phone by the reader.
There are other changes. I spend a lot of time in areas with poor or no cell coverage and toggle the cell radio off a lot. The control center was very easy to access on TouchID phones with only one hand. It is not easy on a FaceID phone. The swipe is from the upper RH corner, and although you can use Reachability to change that, invoking Reachability (a downswipe from the little bar at the bottom of the display) is hit or miss, and even when you get it right the downswipe from the RH edge is more awkward than a simple upsweep with a thumb.
So I'm coming to the conclusion that the FaceID UI/UX is just a lot more motion and a lot more time than TouchID. That's my $0.02 after a little under a week. I think a lot of my dissatisfaction may be just learning new tricks, which is why I plan to keep and use this X until the return period is up in January.
One thing that is NOT an issue for me: the "notch." People, c'mon, really?
TLDR: the return period is currently extended, only you can really figure out how you will like it - buy one and find out, but keep your old phone until you're sure.