I just switched to the plus and couldn't be happier. Mine was even rooted giving me the opportunity to tweak the kernel. The battery life is still twice as good as my S4. Of course YMMV.
Audio is much better also, something I was hoping for as the S4 speaker was tinney and when on speaker phone, not good. Talking about voice calls, music wasn't bad.
Screen is much nicer to read also. Something my old eyes needed. My plus runs smooth with no issues as far as i know, since I don't use all of them. The only thing not happening for me is icalendar not syncing to icloud. All other emails sync fine. But, it may be me and I don't need it. GMail doesn't do push on ios but there are third party email apps to correct that. Again, no big deal for me though.
I am actually amazed at how well it runs with 1gb ram. Something I was concerned about prior to purchase. Android needs at least 2 and then is still not as smooth on my S4. Of course when i look at my 30 or so apps on the plus to over 300 with ATT and Samsung Touch Wiz I understand why.
All in all it is the best phone I have owned. And since my son and his wife are 2 decade hardened Apple users and live at opposite ends of the state, I am now on the same "ecosystem" with them and have more communication with my son over the phones then I did on Android. He is not a Google fan.
Unless you are a heavy custom rom flasher, don't think you can go wrong with the plus.

