Wireless driver issues. Install and switch to different one

Laptop is a macbook pro late 2011 with Broadcom BCM4331 wireless card. OS: crunchbang 11

I currently have bcmi-pci-bridge driver running (It was running out of the box, did not install it). I'm getting slow download speed on wifi (~8 mbps compared to 20+ on OS X).

https://help.ubuntu.com/community/WifiDocs/Driver/bcm43xx (I'm sorry if I'm not allowed to add links) I'm using this website to find the driver compatible with Broadcom BCM4331, so the b43 driver.

So how would I install (can I use the download from Ubuntu or do I have to look for a version for Crunchbang or Debian) and replace the current bcma-pci-bridge driver with the k43 driver.