Speaking as someone who has struggled to find eartips that would stay in place, and properly seal my ear canal as well, I can recommend these without hesitation:
Three important things with these: use the triple-flange eartips, and make sure you put them in correctly; pull the earlobe out as you push them in, it opens the ear canal allowing the eartips to fit in better.
They have reinforced memory-wire leads so the cables loop over the top of the ear and down the back, so if the cable gets pulled, it won't pull the earphone out.
They have angled plugs, so there's little stress on the wire when the phone or player is in your pocket, meaning they last a lot longer; mine are over two years old, and I use them a lot, particularly at work.
Soundwise, for a compact IEM, ( In-Ear Monitor), they produce an astonishing amount of bass, but it's not overpowering, vocals are clear and well-balanced, and the top-end is nicely detailed. I've got three pairs, first pair without a remote, the other two in a sale, BOGOF deal, so I got two pairs for $24.95, and I love them to bits.
Otherwise, I'd recommend Shure SE215's, also with the triple-flange eartips, and for exactly the same reasons, also these have replaceable cables, and you can get them for £75.