Asics Roadhawk FF2 Magic! Leads me fastest record in 21.1km

I broke my fastest record for 7 years. Shoes lead me for 2 hours 36 minutes and 8 seconds @ 21.1 km's Karasuyama city in Tochigi Japan, kept me running 4 minutes 32 seconds per a kilometer's pace. I guess this meets essential requirements for running: light weight, stability and affordable except for one shortcoming of my left ankle hurts for walking not running.