I don't have the armband anymore. It wasn't spectacular looking and I am fine with my phone in my pocket. Since I don't have it I am not sure about the size, but Nexus 6 is a big phone, I doubt it will fit.

For me, regular earbuds never always fall out, the in-ear models only stay in if I push in in to where my ears start to hurt. Because of that I always use something with a hook or a band. I had the http://www.amazon.com/Sennheiser-PMX-685i-Neckband-Headphones/dp/B0094R4Q6Y/ before this, but the wire started to annoy me. So I started looking for something:

• Doesn't fall out and no in-ear hurt
• Since I'm using it mainly outside in traffic nothing noise cancelling. Anything on/over-ear was pretty much out fore me.
• Bluetooth wireless
• Volume / Pause / Next track control
• Decent battery life
• Good reviews
• Sweat resistant

I ended up on this. You can twist the ear pieces a little bit for best fit and you can't really feel you're wearing it. The neckband is really flexible (unlike the sennheiser i had before), which makes it easy to store and also helps comfort a bit. Sound quality is good.

If it is worth the money, that comes down to what you biggest priorities are. For me I couldn't find much that compares and meets my demands. I don't regret buying it.

Jabra makes some models but the get pretty poor reviews:
http://www.amazon.com/Jabra-SPORT-Bluetooth-Stereo-Headset/dp/B005FVNHBI/
http://www.amazon.com/Jabra-SPORT-Wireless-Bluetooth-Headphones/dp/B00DV9O0GC/

Plantronics has a cheaper model, but it needs their custom charger (BackBeat FIT has micro USB) and I don't like the design as much: http://www.amazon.com/Plantronics-BackBeat-903-Headset-Packaging/dp/B00428N9OK/