Brian, unfortunately yes your warranty would not be valid in Canada on a American model Miele vacuum.
I looked at the Miele.ca website, and also watched Performance Reviews video on it. It looks like there are only 3 powerhead models now - The Guard S1, Guard L1 in Nordic Blue, and the Guard L1 Electro + . Plus although the SEB236 is still available to purchase, it is no longer the standard full size PN, that's the SEB228 now. Plus there is no model available with hose handle controls now.
As far as I am concerned, I think the Germans have proven beyond any doubt they truly DO NOT understand the North American market! People wanting the handle controls or a lighted powerhead, they will be driven away to buy a Kenmore Elite instead. And the small bag capacity on the 3 powerhead models was also a bad move - they should have kept at least 1 Guard M1 model, formerly the C3, as a powerhead model. That way they won't drive away pet owners who won't like the small bag capacity. If Miele was smart at all, they need a consulting group to give them marketing info from the North American marketplace to tailor models to our market, NOT drive them away.
