Pros: Good isolation, solid build, portable form factor, great for outdoor use, bunch of accessories, detachable cable
Cons: Overwhelming bass, lacks detail and clarity, pouch feels thin, can be uncomfortable after a while
These days, for $40, there's just not too many good choices out there.
I feel the UE4000 should be a role-model for all the companies wanting to win this market.
First of all, this headphone has an amazing set of features for $40 which includes a detachable cable (super rare), not fully plastic (metal sliders, good foam for the headband), a carrying pouch, a high-quality splitter! With all of the features, I instantly see Logitech won over the crowd.
However, one of the draw back to this headphone is that it is NOT MEANT FOR AUDIOPHILES. This headphone has overwhelming bass which seems to be essential these days in the under-$100 category of headphones and furthermore, it does lack some detail, clarity and soundstage. Therefore, for indoor use, I found the sound quality to be rather muddy.
Interestingly, these problems are solved when you go outdoor where detail, clarity and soundstage is not essential. Furthermore, thanks to the overwhelming bass, what was once muddy, has turned into a huge powerful sounding headphone in noisy environments that is very energetic and fun sounding. If this was not enough, a combination of a portable form factor, good isolation, slim profile headband and the fact that it is lightweight makes the UE4000 ideal for outdoor use. I should make a note here that, the isolation is good enough for most shopping malls and libraries, but they will not drown out lower frequencies such as engine noise.
Lastly, I should note that these are not the most comfortable headphone, due to the nature of an on-ear design headphone.
For a more detailed review, please see my video review located here: