I am flying to Las Vegas for a short trip next month. For a variety of reasons, it made more sense for me to book flights out of YUL and drive up there from Burlington, Vt., rather than booking out of my home airport. I will be departing YUL around 8PM on a Thursday and arriving back around 9PM on a Sunday.

If anybody has insight on the following issues, I would appreciate hearing what you have to share:

1. Since I'll be clearing Canada Customs on the drive up, just to clear U.S. Customs at the airport a couple of hours later (and doing the same thing vice-versa on the way home) is this travel plan liable to raise any red flags with either country's customs officials?

2. If I want to buy a bottle of duty-free booze at YUL for my trip, must I do so before going through U.S. pre-clearance or is there an opportunity to do so afterwards? If before, am I required to pack it in checked luggage?

3. What is traffic like heading from the U.S. border (either Champlain or Highgate Springs checkpoint) to YUL on a Thursday late afternoon/early evening? What about security/customs wait times at YUL?

Thanks for your help!