Which tires for the 300SDL?

Took the car in on Friday. Called today to pick it up, found out that it will probably need to have the head gasket replaced. Also, I was told that a [or all?] of the... Thrust bearings? [I'm not sure if this was the name used] were completely gone, and resulted in increased tire wear. To make a long story short, it needs new tires after 15-20k. The last set of tires that were put on were Michelin M-somethings. They ran about $135.00 [each] at costco. I'd like to put on a less expensive tire [Pirelli P6000 Sport Veloce VR?] without sacrificing much performance, noise, etc.

Just out of curiosity: [I know this is the tire section, but I can't help it] Is it unusual for the head gasket needing to be replaced at 186,000? It's never overheated as far as I know. [One previous owner]

Thanks a bunch,
James

[c43amg]

For the $$ ($70 at Tire Rack in the 225/65/15), the Yokohama V-rated AVS Db are an excellent tire -- extremely quiet (thus the "Db" name) and comparable handling to more expensive Michelin and Bridgestone tires. I put them on my daughter's '88 420SEL and have been very pleased with them.