Planning a trip - best legroom on flights Toronto-St. John's

Hi,

I'm in the early stages of planning a trip to Newfoundland, flying from Toronto to St. John's. I understand the airline options are Air Canada (Rouge & mainline), Air Transat & Porter.

My husband is tall (6'4") and we're looking for the options with the most leg room (money isn't an issue).

Does anyone have any recommendations?