The FiiO FB1 are comfortable and very easy to pop in. More important, they stay in. FiiO employed an effective ergonomic design using rubber tips that fit to the contour of your ear. They almost feel like plungers against your ear. Rest assured, you can do back flips after a sweaty run, and these buds won’t fall out. The tips also come in a bunch of different sizes, so you’ll be sure to find the right fit. The sound isolation isn’t fantastic, but that’s a good thing if you like walking into traffic.