Without knowing what engine is in yours, and your driving style, Cool Carbon is the way to go. If you are a 4.6 or 4.8is this is no part number for your application except for the rears. IMHO you should match front and rear pads to provide consistencies under hard/panic braking.
From the Rockauto.com website
Rotors (assuming 4.4)
CENTRIC 12534050 High Carbon Alloy $63.79 FRONT
CENTRIC 12534051 High Carbon Alloy $46.89 REAR
Pads
POWER STOP 16681 Z16 Evolution; Ceramic FRONT $24.79
POWER STOP 16683 Z16 Evolution; Ceramic REAR $26.79
OR Cool Carbon
Stay away from the slotted and drilled rotors as they are "Eye Candy" unless you are tracking your X5 on the weekends, then plan on upgrading everything to BREMBO BIG BRAKES. $2,700 +++++ They look GREAT and perform as engineered. Not for only street use......
__________________
2005 X5 4.8IS
The
Blue ones are always FASTER....
Current Garage:
2005 X5 4.8is
2002 M5 TiSilver
2003 525iT
1998 528i
Former Garage Stable Highlights
2004 325XiT Sport
1973 De Tomaso Pantera, L Model
1970 Dodge Challenger T/A 4 sp Alpine White
1970 Dodge Challenger T/A 4 sp GoManGo Green
1971 Dart Sport, “Dart Light” package
1969 Road Runner 383
1968 Ply Barracuda 340S FB Sea-foam Green