Pros: 99rmb in China (thats only $17 dollars!). Superb soundstage, strong bass, mids and treble. Great mic, nice design and packaging.
Cons: None yet after 3 weeks
I live in China and have built up a collection of mostly local brand headphones: Astrotec AM90 and AM800, Soundmagic E10, Ecci PR200, Dunu Hades, several different DIY Yuins and (Korean manufactured) Feels Pro 900. I ordered the Xiaomi earphones recently without much expectations - the brand is well established in China and the phones are pretty good but they have no previous hifi experience that I am aware of. After a couple of weeks of using them I can honestly say that they are the best of all the pairs I use - I previous leaned towards the AM800 or the Feels Pro900 but I prefer the Xiaomi's sound to any other options (with the possible exception of the Yuins in a quiet environment!). They have a really wide soundstage, punchy bass but really good separation across the board. As you can tell from my favourite earphones I'm not a big bass guy but love how these sound bassy but balanced) . As a bonus I've also found the mic really clear and the controls simple to use. If you can pick up a pair for $20 or so I highly recommend giving them a try.
I've been using this site for a couple of years but never felt the need to write anything before, there has always better written and more expert reviews available. Actually thatbeatsguy wrote a great reveiw of the Xiaomis which inspired mine. Hopefully this will inspire more and better review the Xiaomis :)