when i first received my dell 1121 (11z with Core I3 cpu), i replaced the HD with SSD
and replaced the wifi/wimax with a wifi/bluetooth DW1702. it never saw first boot with those original hardware. i got the driver from dell.com for the dw1702.
i rely heavily on the bluetooth for google voice calling (using a jabra bluetooth); i can talk and walk away from the 1121. the bluetooth is also my internet connectivity when i'm out and about via nokia 5230 tethering.
bluetooth was a deal-breaker for me if i couldn't get it to work. i know there's a small usb bluetooth that's inexpensive, but i prefer the internal dw1702 as i rarely shutdown and just put the 1121 to suspend/sleep, it's ready for internet in about 5-10 seconds even while the wife is driving 65 mph on the freeway