Some guys over here run 295/30/18 Hankook TDs all around.
I know one person who runs 9.5 x 18 and 10.5x18 TE37SL with these tires. Not sure what spacer he's got, but I know there is one up front.
I am debating in my mind if 18x10.5 with this size tire is possible all around just for track use.