Well, having set-up the phone there's one obvious dislike... the user interface is different to what I'm used to on the S4 and the lack of familiarity is off-putting. But this should soon fade away as I get used to it. Setting up accounts was easy since Google saved my settings from the S4. One downside is that I've got no clue how to transfer stuff to it via NFC from my S4. Tapping the back of the phone does nothing on the S4 screen. Maybe I'm just dumb.
Another thing is the fact that widgets on existing apps have yet to be updated for the 5x5 form factor. So I've got some weird looking 4xN widgets. I'm wondering whether we can change the 5x5 form factor to 4x5 or something. It's handy to have more icons on screen, but the widgets don't fit... ugh. I'm already missing the battery saving mode from the S4, the battery came at 50% and its apparently used up a quarter in these few hours of fiddling around with settings and trying to set the phone up to a similar level to my S4.
The micro USB port looked a bit smaller than usual to me, I was worried it used a different charger, but I plugged in the charging cable from my S4 and it works. Once I get it to 100% I'll start to see how the battery life is. Can't check it properly without a full charge. I'll also be able to say how long it takes to charge.
I'd also take a picture of this, but CBA, the microSD and SIM slot are in the same place. I.e. the microSD slots in just above the SIM. I was initially confused about which slot to put my SIM in, but they have a guidance icon next to the slot to tell us what goes where.