For $10 plus shipping??? Yeah, these are good.
Build quality: wayyy better than anything else you'll find at this price, the cord could be better, but, again, $10.
Features: the in line remote works, comes with extra ear pads, it makes sound, what more do you want?
Sound: the main event, they're more than a tad bright, and have strong bass, their description stating a "V" shaped response is very accurate. The imaging and soundstage is far better than I expect out of earbuds and exceptional for a $10 price of entry. Easy to drive with my phone (LG G6, YMMV). So, not accurate sound, but a very entertaining sound signature. Excellent for rock music, bass is great for electronic music, just keep in mid that they are bright so depending on what you listen to they can be fatiguing over long periods; but, again $10. Turn down your treble knob or use an eq to knock down the top octave and these sound incredible for the price, and even for five times their price.
Things I'd like to see improved in a future revision: the cord.
TL;DR for $10 these are the best value on Massdrop, period.