I have an S8+ and my comments would be:
Amazing screen. AMAZING. Undescribably good. When you use another phone it's like "what is this brick?". It's like seeing an old CRT screen on a PC.
Battery life good.
Performance excellent.
I don't use Bixby but that extra button is annoying. Overall I don't really notice bixby, and have no expectations of it. It doesn't come up unless I press that stupid button.
I have a case on my phone (Samsung's alacantra cover) so the finger-print sensor is much better deliniated than "naked", and as such is not a problem. Can see though (when I take the cover off) that it is a pain.
I don't have any problems reaching the sensor though and have average size hands (I use medium to large size gloves).
The fingerprint sensor is awesome though for unlocking the phone, etc. I use glasses so the iris sensor is a no-go.
Will just point out that the comparison to the Huawei phone (4GB vs 6GB RAM) is kind of pointless. People will buy the S8 because the design and screen are phenomonal. The amount of ram is not measureable in terms of every day performance. 64BG of storage is the important one an should be fine - plus the SD card.
It's still not as fluid as an iPhone but at the same time you don't feel like you have to own only i-products.