My first set were Continental Contisportcontact 5 which came from factory, they were fine no issues as such but towards the end one tire had a bubble and another was just losing air through some fine cracks in the side wall. The roads in my city are shite so what applies to me might not apply to everyone. Now I've switched over to Michelin pilot sport 4s and I can tell you there is a huge difference between these two. PS4s are the best tires I've ever owned, a lot more responsive and grip levels are phenomenal. The contisportcontact6 are out now never tried those so no idea, don't know anyone who's tried those either so can't comment, maybe they are better than CSC5? I'd recommend PS4S blindly though!