I am a fellow Canuck who has owned SONOS for over 2 years. Initially purchased some from National Audio Video in Edmonton. Have since purchased some at Future shop in Winnipeg, MB when they were carrying the product and since added some more zones for NAV again. Best Buy will be carrying bundles also.
The product is excellent at what it does. WAF is extremely high. I hardwired all my zones and the system has been solid. I am up to 7 zones with 2 contollers. Recently one of the off warranty Zone Players has been suffering from hard lockups and it will be going back to Sonos for $150 Repair/Exchange.
The system only needs access to compatible music files on SMB network shares to function. Check their user forums for NAS compatibility and recommendation. Initial setup is easily done on a PC using the Sonos Desktop software.
Currently there are some compatibilty issues with the Windows Home Server RC1, but I am confident they will find a solution for this in the months to come.
Yes the cost is high, but IMHO there is nothing out there that compares. They'll have to pry this thing out of my cold grey hands.