Sony almost always delivers when it comes to good quality audio products and these headphones are a great example. These headphones fit quit well and have different size plugs depending on what works best for you. The sound quality is good, but a bit on the lower end in my opinion. The clarity is lacking a bit and there is almost to much bass, but over all has a great sound and nice isolation. And for under $20 you really can't go wrong.
Pros: Price to performance ratio, clarity (at this price), quite balanced, cable never tangles or kinks
Cons: Poor isolation with stock buds, bass may be a bit shy if you're fussy
I bought these in my early days of earphone obsession when I was a basshead - coming from a pair of House of Marleys which had lots of bloated bass. Didn't really think much of it then due to its flatter bass but love it now I've reformed from my basshead days.
As I said if you want to be really fussy about the bass quantity you could - but for me the low-end is very pleasant for a pair worth 30 bucks. Bass is well defined and mostly taut.
The mids are great on these - not muddy or unclear. Vocals come through really well
Highs are ok.
If you want to get the most out of these you'll need aftermarket buds. Isolation is almost non-existent from the stock buds
Pros: Price, surprisingly neutral and accurate, not muffled
Cons: Not enough isolation to my liking, you will mistreat them just because they're cheap
I'm absolutely amazed at the price of these, with a fancier/heavier enclosure and more isolation these would feel like formidable audiophile universal IEM. Right now they punch way above their weight, both figuratively and literally. They aren't prone to hissing, and I haven't heard severe frequency response deviations with multiple sources, including straight off an integrated sound card, several smartphones, Sansa Clip Zip etc. Very easy to drive.
I've destroyed several pairs of these by accident just because 9.90€ earbuds are so easy to use carelessly. My only minor complaint is the way how buds tend to slip out of my ear, but that's the fault of my ear, not buds.