My girlfriend upgraded from her Note 3 to the Moto X Pure when I upgraded at the same time from my LG G4 to this and we're both EXTREMELY satisfied. Dev support is on the rise so you'll have a few choices in ROMs. I'm currently rockin' TruPureXMM v2.5 with Franken Kernel using his Battery Profile settings, xPosed with GravityBox, Amplify & XGPM and can honestly say I couldn't be much happier with the experience overall.
We have the 64 GB models and neither of us use an sdCard since it's been more than enough for us. Google Photos keeps our photos stored and Google Play Music is our choice of service (Family Plan for $14.99 a month) which lets us stream our over 23,000 song collection and gives us access to any song on Google Play with no ads and since we have T-Mobile the music streaming isn't going against our high speed data, which is very nice. As other are saying, you will enjoy the dual-front speakers, the screen is great, and battery life is within reasonable acceptance. You can squeeze more out of it fairly easily with some tweaking and the quick-charge is INSANE. You can't beat the charger that comes with this phone.