To change my fog-lights to HID, I needed to change the housing since it wouldn't be able to take the heat:
Subaru Fog-Light Housing (H11)
Purchased and Installed at:
Autokozmetix
Here's the difference between the OEM Fog-Light Housing and the Subaru one, it seems to be darker:
AC Tech Fog-Light HID Kit (6000K - White)
Purchased and Installed at:
Autokozmetix
The fog-lights look brighter than the headlights in the pictures, but in reality it's just about the same. Comparing it to the stock halogen, it is a lot brighter and illuminates the road more consistently when driving at night.