Not sure what a "flimsy" device is suppose to be built like when it is actually a delicate device that is used in ones ears. I suppose you could build it like a tank like SE-Shure series but then it is so robust many have to remove after 15 minutes it is so painfully robust.
Bingo...well said. Plus I've owned the W3s, W4s for a number of years and yes, they were light and very comfortable, but they also lasted and lasted! My W60s seem to continue in that tradition.