I have two of these tires for sale in great condition. $280 picked up for both in North Quincy. $200 picked up if you grab 'em within a week of this post!
These two tires are in stock E46 M3 rear tire size. They can probably be used on E90s also, depending on your tire/wheel setup. Only used them for a few hundred miles before I swapped over to winter tires. Approximately 9/32" tread on each tire last time I checked. I can post updated tread measurements and photos in a week and a half.
Size: 255/40ZR18
Sidewall Style: Blackwall
Serv. Desc: 99W
Load Range: XL
UTQG: 400 AA A
Price (new): $192 each
Full specs at Tirerack:
http://************/7wqde7d