Pros: Sound quality, price, comfort, durability
Cons: Cable, jack
I was looking for an inexpensive pair of on-ears and, after reading some positive reviews on the "flats", I decided to give them a try.
Packaging: simple as it gets. No accessories. Just the earphones in a plastic package.
Build quality: materials are on the cheap side, but with no major concerns. I have been using them for almost two years now, and they show no signs of tearing. My only concerns are related to the thin cable and its insertions on the earcups, which seem somewhat flimsy and fragile. The jack seems to be taken from some 1990's design, and looks too protruding for portable use. The folding system comes in handy to store the phones in a messenger bag or backpack.
Fitting, comfort and isolation: they sit comfortably over the ears for many hours, except when I am wearing glasses. But this is the problem with most on-ears design. Also, they need to be precisely placed on each ear, to avoid differences in the sound stage. The first time I used them, I got worried I was sold a defected earphone, because the sound was unbalanced. It turned out that the left cup was slightly placed to the back of the ear in relation to the right cup. I didn't expect to have these kind of problems with on-ear phones, as they are much more likely to happen with in-ear designs.
Once put, they stay put. The compression is about right and the metal bands are secured in a tough rubber material that helps keeping the phones in an exact position on the top of my head. This is an important thing for me, because I shave my hair. For instances, I could't hold the great-sounding B&W P3 on my head: that cloth band was too slippery.
The isolation is quite good, due to the closed back design.
Sound quality: these earphones are not demanding. They will sound right whatever source you're using. Either a computer, DAP, smartphone, dedicated amp, hifi stereo component, you name it. They are also very forgivable of the recording quality, being a great choice for low-quality podcasts or music streaming service.
They will shine, however, with good quality recordings on good quality equipment. The bass is well balanced, offering good depth and definition. The treble is refined and the mids are present and well rounded. The biggest drawback is that they start sounding a little bit congested when the volume is cranked. I attribute this behaviour to its high sensitivity.
I gave them some 30+ hours of burn in and listened to them again. They seemed more articulated, crisp and well balanced.
Then I went to compare them with a 7x more expensive pair of Senns PX 100 and... wow... the flimsy JVC's kicked ass. They sounded way better than the Senns in every aspect, including tonal balance, timbre, attack, decay, micro and macrodinamics and stage.
Conclusion: of course there are many better earphones out there for just 40 or 50 dollars more than what these costed. And many more in the 100+ price range. But for those on a budget, considering some earphones up to $50, spare yourself some cash and go for the "flats". Don't worry, they won't break unless you stress them to the extreme. I've been using mine on a regular basis, for travelling and such, and they look as new. Don't be fooled about its flimsy looks: they are tough and sound amazingly good with every equipment and every kind of music/audio.
Equipment used: Sansa Fuze v2 RB, Nokia Lumia 925, Cmoy DIY amp, Radiopaq Jazz, SoundMagic ES-18, Sony MH1c, Awei ES800M, Sennheizer PX-100-II
Music listened for this review: Mayra Andrade - Navega; Mayra Andrade - Storia, Storia; Crosby, Stills & Nash - Greatest Hits; Sufjan Stevens - Illinois; Stromae - Racine Carree; Pearl Jam - Ten; Cesária Évora - Nha Sentimento; Regina Spektor - Begin to Hope; Ibrahim Maasouf - Diagnostic; Llasa - The Living Road.