Same here. It's my daily driver. It does everything that a larger phone does (except NFC and WIFI hotspot) and it fits in the coin pocket of my jeans. I can sit on this phone and it does not break (granted I have the mophie extra battery case around it). Oh, and I seldom need the extra battery since I'm running a verizon sim and the battery even without life mode lasts all day if I'm not on it constantly. This is the answer to OP's question, although it's a shame that it's slightly sim limited (can't change the APN so can't use visible) and there apparently won't be any updates or newer models. The only other viable small option is the mini iphone, which while it fits in my coin pocket is not as small as I'd like and will be much too easy to break.
How are you finding the battery? It seems this is the most common complaint.
Edit: and also, what's the software support story here?
I have on too! It's too slow for me now to use daily, but I do bring it with me while traveling as an emergency backup. I really wish they would release an updated model.