Gasket and seal coverage
Make sure that you're protected against gasket and seal failure. A warranty without gaskets and seal coverage will exclude many engine or transmission repairs as the fault of a seal failure first, and a mechanical failure second, and you'll end up paying the thousand dollar repair bill yourself/
Look for a policy that will pay for repairs at any licensed shop or at least one that has a large network of affiliated repair shops across North America. If you're traveling far from home, you need to know that you can get repairs wherever and whenever you need them (You can use FoundLocally to check out such shops across Canada).
This is essential if you plan to sell the vehicle before extended warranty expiry. Used-car buyers will pay hundreds or thousands more for a vehicle with warranty coverage that will pass over to them.
If you break down, will the warranty cover the cost of a tow to the garage? This can add hundreds of dollars to costs of repairs of the warranty's lifetime.
Hours of service
Are they open 24/7/236 or do they have limited business hours