These laces are a great idea but really consider how short 30" laces are before you buy them (I did not realize how short that is for shoelaces). I tried stretching them into my sneakers and ended up with the end slipping out of one hand and the hard end of the other lace slapped my fingers like a hardened rubber band slap--oww! Won't work for me--I returned.  I will say for the half-second they were in though my shoes were really comfortable--I have some walking shoes that are really fitted (purposely I bought them that way for support) and the laces gave them just a little give in just the right places so my feet could breath and I could have pulled my feet in and out of my shoes without untying them but not have them fall/shake off (at least until the laces flew out).  All in all, good product if you can use it.