First off all,I have to say that even before I put them on,I noticed how light they were. How light?I don't have a scale in my apartment,but let me tell you,they are feathery. Very comfortable,no pinching or rubbing was felt anywhere. The lockdown fit is yet to be determined,as I didn't really buy these for running,although I often run to and from the gym in them. I wear them kinda loose,so your fit may be a bit different. They got soaked in an unexpected downpour,so I threw them in the washing machine and let them air dry (took about a day) and they were no worse for the wear...I found out that the higher the number (250,400,500,ets.)denote a higher level of cushioned depending on your needs. Overall,a really good shoe.