Originally Posted by
N1120A
Even with bags, I'd lean toward the train, and just carry-ons makes this a no-brainer. Take the train.
As for customs, they really won't care. Indeed, you are a citizen of Canada, so the CBSA really has no interest in grilling you beyond your duty free allowance.
They will ask you how long you intend to stay and sometimes they ask where you are staying. Neither question is any business of theirs, but sometimes to go along you have to get along. On the return, sometimes if your destination in the USA is not near your home or doesn't seem along then way, CBP will ask why. You have good reason: avoid ridiculous Canadian air fares. If they don't buy it, be prepared to show copies of screen shots taken when you were fare shopping.