Hello...E10 has a much more rounded profile than the E09..hence still being able to give suitable lean on the black stuff!!..I have used the E09 before and agree it's a great off road tyre but it has a much more square profile which doesn't equal as good road performance as the E10,but hey I'm just trying out as many as i can till I find the one that suits my daily commute as well as the trails as often as I can!..