They work well in my used running shoes if placed on the top of the worn lugs. I don't feel any lumps in my shoes. They, of course, mar my hardwood floors, necessitating removal when I enter. On glare ice, which covers my steep gravel 900 ft. access road most of the winter they're GREAT, on soft snow I really can't tell much difference (the same applies to my studded snow tires). I haven't noticed much wear from walking on the cleared pavement for the remaining 1/2 mile to my mailboxes every day. Also, in years past I have worn out 2 pairs of non-carbide traction devices on the same route. These are holding up well and into their 3rd year.