Whirlpool GU2700XTSS / GU2700XTSY 24 in. Built-in Dishwasher

My husband and I purchased our WP / DW in June, '08.  It has not cleaned dishes thoroughly, glassware & silverware became stained with foggy spots.  We've had no less than six service visits since installation and, after the replacement of a rinse dispenser, soap dispenser, heating coil, and power unit (pump motor) the end results have been the same.  Whirlpool customer service has been useless and rude, said whirlpool would do nothing about the situation.  i've had to soak my glassware & silverware overnight in a distilled white vinegar solution to remove stains.  This is a veritable LEMON.  The retailer from we purchased this appliance in Placentia, California, washed their hands of any responsibility to us by say ing that Whirlpool would not stand behind their product.  Consequently, I would not recommend the retailer or any Whirlpool product to anyone.