May I ask you why you are interested in BT4.0 earbuds? From what I discovered testing various wireless headphones, in general BT4.0 + aptX codec should give you the best sound quality, but others do their own proprietary decoding which is on par or even better.
If you are looking for the type of sports wireless headphones as in your Anker BT4.0 reference, you have much better choices. First of all, take a look at my detailed review of Plantronics BackBeat Go 2:
http://androidforums.com/android-ac...ckbeat-go-2-wireless-earbuds-w-lots-pics.html - in the second post I did a more detailed comparison between BBG2, JayBirds BlueBuds X and Anker BT4.0. As much as I consider myself Anker fanboy (their batteries are the best), their wireless headset was a miss. They don't manufacturer any of their stuff, everything is licensed and re-branded under their name. Between those three, BBG2 have the BEST sound quality and they are not even BT4.0. In addition, they have really cool charging case pouch and free app that lets you know remaining battery level. BlueBuds are popular, but their sound is not as crystal clear as BBG2 and they are a lot more expensive. Anker is the cheapest one, but it uses proprietary charging clip (you loose it or forget it going on vacation - and you are stuck). Plus, it's remote is not as good, and BT reception cuts out a lot.
So, here is an example of BT4.0 headset performing a lot worse than BT2.1/BT3.0 headsets. If you are into a sports style of those wireless headphones, BBG2 is the way to go.
Also, LG+ HBS-730 is great. Not the best sound quality, but a very unique design, lots of controls under your finger tips, and amazing battery life. It's still Amazon #1 selling wireless headset, and now on sale for $41.99. Check out my review links in signature or in a sticky of accessories forum for the review as well.
