I had a chat with Ken Whellems one day about this because there was an entire thread where people were saying different things about the warranty, and noone really knew for sure. I had phoned one time and gotten the same answer as you Lundvike. However, Ken corrected me.
Springbrook will honor the US warranty provided that make/model of rod is AVAILABLE here in Canada, and you're the original owner.
*edit* An example is the 4 piece NXT combo on the templeforkflyrods.com website.. they are made in the US, but not Canada. So if you purchased a 4 piece NXT combo in the US, brought it back home here and broke it, you could not get the piece replaced because the 4 piece Signature Series that Springbrook has here is a different rod.
Same goes the other way.. TFO USA will honor the warranty of a rod made in Canada as long as they carry that model and you're the original owner. The 2 piece Ti series would probably be an example of a rod you couldn't get replaced in the US, as I don't see it on their website at all.