I had my Subaru dealer install the cabin filter yesterday. It was their 1st installation on a 2005 Legacy.
The installation went from 6:00pm - 8:25pm (2.5 hrs).
I was charged for 1 hour of labour.
I think the 3M Filtrete filter material is as good or better than Subaru's cabin filter material.
I use the 3M Micro Allergen (red package) material for the basket filter in my home furnace.
Canadian Tire sells the Micro Allergen material in a sheet that's 30" x 60" for $25 CDN.
This would provide at least 21 filters for our cabin air filter.
It's the exact same material used in the DIY on page (1) except its flat.
This is the product:
http://products3.3m.com/catalog/us/en001/government/innovative_solutions/node_GSFNS893K7gs/root_GS3RBW6QFVgv/vroot_31S2JJ7584ge/bgel_GS73HX18NKbl/gvel_77KSFNB0FZgl/command_AbcPageHandler/theme_us_innovativesolutions_3_0
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