whatever you do, stay with OEM for the M instead of replicas. It may cost $1k more in the end - maybe more depending on the style, but you don't want to be messing with heavier replica wheels for this fine-tuned machine, or wheels that may or may not be out of round like the headache I had to deal with.

Cost really depends on the style. Just to give you an idea - BMW wants $5k for 21" style 128s. Something like $3k for the 20" style 214s with rubber (think $2k just for the rims).

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'08 X5 3.0si - Alpine White / Saddle Brown interior
Specs: Sport Pkg, Premium Pkg, Tech Pkg, Comfort Access, Aero Kit, Style 433 staggered 20s on Conti DWS
Mods: Carbon 35 tint, LED angel eyes, GP Thunder 7500k fogs, H&R 20mm/25mm spacers, clear reflectors, gunsmoke-tinted taillights
Coded: Digital speedo, windows/sunroof/tailgate close via keyfob

X5 pics at Flickr