I probably would buy it again...for several reasons:
1 - Sprint hasn't even come out with a newer device in several months (glad I didn't try waiting for the Xperia Z3!)
2 - It's a great screen...the photos are nice (though in bright light things tend to wash out a bit...but I haven't messed with the camera settings much)
3 - I've grown to love the size even though it's the biggest phone I've ever owned
4 - I've not seen any lag and the worst bug I've experienced is the other day my notification tone stopped making noise for some reason. A restart fixed that and it hasn't happened again.
Things I'd hoped I'd grow to love but don't yet:
1 - Back buttons. I get that they make sense and it's kind of fun to watch people try to figure out how to turn my phone on...but they still feel awkward to me and I honestly miss the placement of the power and volume buttons from my Galaxy S3.
2 - The knock-on and knock-unlock. Sometimes I just wanna press a home or power button but, oh yeah, it's on the back...which again, I'm not in love with.