I have Nexus, so I always come back from Toronto or NF via the almost-deserted Whirlpool Bridge. I do not use the Whirlpool Bridge to go to Canada because I have not gotten around to depositing some money in my Nexus account for the toll. Since I typically go over to NF on a weekday during the day, the Rainbow Bridge usually works fine.
If you are thinking of getting Nexus, there is now an additional incentive. You will automatically qualify to become a
TSA-Pre traveler. I recently used it to fly out of BUF. Going through airport security, I kept my shoes, belt and jacket on, and did not have to take out my laptop or fluids. Coming back from overseas, I can also use the much shorter
Global Entry lane.