I have had my S8+ for a couple of weeks. I finally upgraded from my S4 because it quit charging. That was about 2 months ago and I have been using the lowly iPhone S6+, which I immediately hated and have despised ever since.
My impressions of the S8+ are that it is perfect for what I need. I'll refrain from comparing it to the iPhone because IT has so many inferior qualities that ... well, there's a reason we all have Androids! The additional RAM of the S8+ overcame all the issues I had with the S4. The newest Android operating system is a little better than the one on my S4. At least I can save stuff to the microSD card on this one, and the S4 had not allowed that after an OS update. I am using the same SD card, so I know it was not a card issue.
Some of the things I like: I can group my contacts and assign ring tones to each group. My family has a few bars of the Pointer Sisters "We Are Family" as the ring tone. My CPA & banks have the opening from Pink Floyd's "Money" as the ring tone. My doctors and pharmacy all have a siren for their ringtone. My co-workers all have the default AT&T ring tone (because that is my employer), and everyone who is not in my address book has a few bars of Chuck Berry's "Johnny B. Goode" as the ringtone. I do like this camera better - no so much because of it's greater resolution (seriously, the S4 took very adequate pics for my needs), but because of the new features.
I like that I can access files that I could never do on the iPhone (ok, I lied). I keep a copy of my divorce decree just in case the ex wants to argue a point. I keep my Excel spreadsheet that contains all my passwords (it is password protected, too). ALL my music is available on my SD card without any issues, whether I copied it from CDs, recorded it from vinyl, or downloaded it from anywhere at anytime.
One of the things I like is that it has a certain amount of water resistance. I was lucky when I walked into the swimming pool with my S4 in my pocket - it only took 2 days for it to dry out adequately to start working again.
One of the things that I do NOT like about it is the Edge screen. When I am playing certain games, I hold the phone in landscape orientation, and my right hand pinky finger tends to activate something on the edge.
Another thing I do not like about it is it's size. Actually, I have a love-hate relationship with this phone's size. I like that it is bigger and there is more screen territory. I do not like that it is bigger and does not fit into my belt pouch like all my other phones. I actually have to put it in a zipper slot instead of the clip-strap slot, making it more difficult to see who is calling. But, I will sacrifice the inconvenience for the clarity.
I swore I would never buy another Samsung product when my Samsung pad quit charging a month after the warranty expired and Samsung refused to fix it - even at my own expense. They said they could not replace the charging port (I suspected my daughter had broken the microUSB tab in it). But, when I finally had to break down and get a new Android, there really was no other choice, at any price.
Hope this helps.