The Clement LAS center tread is not going to hold up to pavement. If you want those side knobs for trail riding, look at the Ritchey Speedmax comp. I've been riding them for years on the pavement and the center tread holds up really well. It's also pretty good off road except for mud. The 700x40mm version is 35mm wide on 15mm id rims with a 100mm bead to bead distance. They are also only $20.

But what you really should do is have two sets of wheels. One for mixed riding, another dedicated to road riding.