I was just starting to enjoy these, having got over the issues with the fit, when the right hand driver failed. After 24 days! That is feeble. Also paint has worn off on both sides. My ears are not abrasive, this is just very low quality product. Really annoyed.
edit 29th August 2021: I'll leave the above in place. But Drop customer service has been speedy and helpful. I asked for a return and a refund. They suggested a replacement at no cost to me. OK, I liked the earphones enough that I'll give it a go.
I'll just reiterate some thoughts expressed before the things failed, but subsequently deleted:
The sound is great. If you can get the damn things to fit! I've been using IEMs for 20 years and these are the absolute worst for reliable fit. It's not that they're uncomfortable, it's that the sound changes *dramatically* if you don't get the perfect seal with the IEM in the perfect position. It's crazy. I've used Shure, Klipsch, Vsonic, Massdrop, NuForce, Sennheiser, Flare Audio, RHA, Xioami, Sony, Panasonic, JVC, Samsung and a bunch of other stuff I can't even remember. These are the worst for depending on perfect fit. If you get them just right then they are beautiful. Really neutral. Neutral in the sense that you get that beautiful music piped right into your brain just as it ought to sound, not neutral as in boring! But don't sneeze. Don't chew. Don't yawn. Don't speak. Don't even move. In fact, try not to breathe. If the IEM or the tips move or your ear canal flexes by a fraction of a millimetre all bets are off.
Oh yeah, these are *way* too insensitive for typical smartphone use. They are the quietest earphones I ever tried. That's OK on typically overly loud modern recordings but for classical and jazz it is hopeless. Mee Audio invented an IEM that doesn't work that well with the billions of smartphones on the planet. Doh.
These have quite high impedance for an IEM and the sound appears consistent regardless of the output impedance of the source, so these are actually very good with home amplifiers and similar.
The isolation, if you can get and maintain a good fit, is extraordinary. Really remarkable. Better than any Shures. I guess Etymotics might be better, but nothing else.
edit 12 September 2021: an illustration of what your PX might look like after 2 or 3 weeks! On the left is how the purchased item appears after just a little real world use (I do not have abrasive ears(!) and always use a case). The one on the right is after 30 minutes or so polishing with fine and superfine foam backed abrasive pads. A little more care and work with microfine abrasive pad and it will look really nice.
Would recommend to a friend.