At 1200 miles...they should still look all but new...
In how many years are you selling your X?
With any luck...the old tires will be dried out and cracked with age....poisonous spiders will have nested in them, West Nile Virus Mosquitoes will be waiting, and hungry, Mice, carrying Hanta Virus, Rats with Bubonic Plague, Rabid Bats, Rabbits with Bats, Bats with Cryptosporidium contaminated guano, Janet Reno....etc....
As I said...Grabbers are cheap tires...you are not geting much for them either way...if you want and can afford new meats...do it now..if you need to rent the Grabbers untill you have the $ for Boggers, etc... (
), Then drive them until as bald as you need them to be.
If a premium trade will be the slight edge you need to pay for the new ones...trade sooner...its not an exact science...its an art.
