Wirelessly posted (BlackBerry9650/5.0.0.1006 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/105)

No problems whatsoever. If you're a Canadian citizen, Canadian customs laws do not allow for a Canadian to drive a US-plated rental car into Canada, but I do so once a month and they're ok with it since I reside in the US. If you're a non-Canadian, go on up - if you have any questions, just ask Avis. But it's almost something they see everyday, especially stations near border cities (note this doesn't apply to Mexico, of course). I've even seen one-way drops before -- I was given a Manitoba-plated car at LAX a week ago.