Conti GP 4000S Mileage

200 lbs.  I get 2000 miles (1.5 years) out of them.  Except for when a tube blew out last year.

Hate to hear that....I posted on this a week ago but decided to try them again...I had a blowout within 50 miles of use in a race resulting in a DNF

Keeping my fingers crossed that this set will be OK

I don't really track mileage but i've gone through a few sets this year so I would say that it's around 2000 miles for me. I typically only replace the rear and rotate the front tire back and replace one tire at a time.  they rate or wear on the front/rear is pretty different for me. 

So far in the few years of using them for training on the roads I've replaced the rear 2x to 1x front. I didn't track the mileage I used the wear dots to gauge.

I only race on a newer tires as they are the most aerodynamic.  I read the aero properties fall off pretty fast once they start wearing.

Depends how you ride on them and what type of road surface.  You will wear your rear tire out a lot faster if you spend a lot of time out of the saddle while rocking your bike or ripping through corners.

ETA:  Also depends on how much wear you are willing to ride with.  Some people ride their tires down till they are pretty squared off and thin.  Again...okay if you're just riding in a straight line on clean roads...not so much if you expect to do some hard cornering on roads with debris.