Just had the water pump replaced on this car and now it seems the head gasket it blown. I was looking into K&W Metallic Block Seal, but wanted to know if anyone with a Saab has ever tried this.

The car had no symptoms, never overheated that we knew of and now has water in the oil.

Any constructive feedback will be appreciated.

Have you had the car pressure tested to make sure that it's actually the head gasket that's causing the oil & antifreeze to mix?

Yes... had it tested and they said it's indeed the head gasket.

The block seal may or may not work, depending on the severity of the damage to the gasket. You can try it but don't cross your fingers.