Already i've used ChatGPT and Copilot asking for a comparison for service and refunds, and it provided some Trusted Reviews feedback.
Trip.com and Expedia have the better service

I've used Expedia couple of times in past and lucky no problems with flight But this time, prices are considerably higher than Trip.com
Trip.com haven't used, but reviews are mixed some say service & refunds good, some bad. Low prices they show might not be obtainable , yet they charge your card, then you have the hassle of trying to get refund.

Want to do a direct flight from Canada to USA -- seems there would be less chance that Trip.com or Expedia, screws up one direct flight....but is airline or weather or mechanical problem cancels the flight, re-booking might not be fast

Thanks.

Plan to stay couple days in USA, then have second flight to Mexico (already ticketed)