je11yMy EarStudio ES100 is practically silent with the MD+... Way costlier and somewhat less sleek obviously (and short 2 pin cables can be a PITA to find), but you do gain a bunch of features, better codecs, better battery life, and the versatility of being able to use it with other stuff.
I've been using that kinda matchbox sized clip-on BT receiver for years (Sony MW600 circa 2011, Fiio BTR1, etc.), I take a look at these necklace/cable kind every once in a while but there's always something that looks like a downgrade, and I use the former with on ears and Koss KSC-75 as well anyway.
ImpulsesI actually just picked up the ES100 last week and I'm not looking back! It leaves a bit to be desired when it comes to build quality, but more than makes up for it with functionality/features. Really surprised how much power this tiny thing has, there really isn't anything out there that competes with it in the same price range right now, as far as I know.
je11yBeen using mine for over a year on the road and at the office, there is nothing wrong with it's build quality. They opted for lightweight components and I support that as I usually clip it to my shirt and wrap the excess cabling around it. Never feels like it's pulling on my clothes, a "better build feel" would have made it heavier.