Brian, double check with them if they are considering the right location of the filter in the x3. Even at $80 an hour, i wouldn't think that's a half hour job. You don't want any "surprises" after the job is done!
On Most other bimmers it's under the car and that would be about right the quote.

__________________
"If everything seems under control, you're just not going fast enough"
-Mario Andretti.
___________________
River City Bimmers Chapter
2005 X3 3.0i ZPP, Htd seats, Htd strng, Black Sapphire on Terracotta.
1995 ///M3 Coupe, Lux, MT, Htd seats, Cosmos Black on Black.