looking for advice !!!!!!

I owen a 04' negaro blue s4 , great car but with the great car came a big problem !

my car was purchesed six monthes ago with 10k , a month ago we noticed a coolent leak and we were advised by audi to bring the car in to be topped off .
Few weeks went by and the problem came again , we took the car to audi and after a few days they discovered to our disappointment
that there is a leak through the freeze plug..........
For the problem to be fixed there are going to be 2 weeks of hard work needed, which include removing the engine out from the car, taking it apart replacing a small plug and putting it back together .....
here is my question- has anyone had this problem occur to ? this is a top of the line car , and a problems like that should not happen after 20k . any sugestions????? all this time the car was kept and driven and with very high care....