I've got a Sony SW2. It's just an extension display to the handset(s); displays notifications for Gmail, Hangouts, Twitter, Facebook, Whatsapp etc, acts as a remote for my music player and camera, accept/reject calls, access calendar info etc and does the job it's designed for well. Best of all, it works with all three of my Android 4.x handsets.
It's not the daintiest device though; much less bulky than the Gear but still with a larger face than conventional timepieces. I get around three days use from a 100% charge before it demands recharging.