Ok so my phone is finally ready. Restored from IP6s+ & iOS is updated to 11.1.
My 2 pesos from using the phone for barely 10 mins. Face ID is DAMN fast. Screw the Tom's Hardware Guide reviewer who b*tched about it supposedly taking 1.8 secs compared to Touch ID which supposedly took 0.9 secs. No normal person with a life would go around timing it like he does.

Fact is, based on a normal person's day to day usage, it is fast.
I had tried using Note 7's retina scanner before and it took forever and yet could not recognise my eye balls. So yes, in comparison, Face ID works and is fast.
Put the phone on my subwoofer and looked down on it and it could recognise my face. Very low light condition too, gonna rain any moment and I purposely turned off my living room lights. Recognition was just as fast as if I have the lights turned on and the phone right in front of my face. Haters will be hater but let's face it, Face ID works lah.
As for the issue about twins, as you can see on Youtube, for every video showing Face ID working on both twins, there is a video showing Face ID works with only one twin. Anyway, seriously how many people here complaining about the twins issue actually have identical twins? Most I am sure, are just b*tching for the sake of b*tching.
Black notch? Barely noticed it. Like I said, I've only been using it for 10 mins now so I may have different views in a few days time esp if I start using apps that are not optimised for IPX, but as of now, I seriously almost did not notice the notch.
If you are going to take a ruler and measure mm by mm, yes viewable area on 8+ is larger than IPX, nothing new, mentioned before. But if you just enjoy it as it is, to me, the slightly smaller viewable area is really no biggie. Again, that's just me. Others may fuss over 1 mm less viewable area so to each his own.
What I appreciate is that its smaller than my IP6S+ and fits into my tight jeans pocket. With my previous phone it was always either jutting out of my pocket or poking into my hip. And it was impossible to remove from my jeans pocket without standing up. No issues with IPX. If that means sacrificing a teeny weeny bit of screen real estate, I'm fine with that.
Now the litmus test is the battery. 10.3.2 was the last OS on my IP6S+ which was ok. 10.3.3 killed the battery and there have been tons of threads here about how iOS 11 is even worse. So fingers crossed.
Thus far if I had to complain about something I guess it would be the fact that since the earphone port is gone and an adaptor is required, my earphones can no longer fit into the neat plastic box that the earphones came in. Or if I want to use that box, I'll need to keep the adaptor somewhere and hopefully not lose it. I guess Apple's whole idea is to make ppl buy their Ear Pods.
That plus the fact that I need that big brick of a 29W adaptor for fast charging. At home no issues but once at work its a pain. Like most ppl I just plug into USB on the office PC and I'm expecting the charging to be slow as hell.