So up until last year, we could choose our Air Canada seats for no cost, but like every other airline, they now charge to choose ahead. And unfortunately, they used to fly a 2-3-2 config from Halifax and now fly a 3-3 config (Boeing 787 max), so now no 'me and hubby with our own two seats' option.
Anyhoo, I was humming and hawing over paying the $55 cdn for the preferred seats vs the $30 for the others (I didn't want to get stuck with two middle seats apart and figured the prudent thing to do was pay ahead). I asked AC on Twitter the difference and the reply was the preferred have 33-34" pitch, while the others are 29 or 30. Wow...what a difference that extra few inches makes. You can actually bend over and not have to contort your head sideways to reach the under seat bag. (For an average height person like me). Even tho we are lucky and our flight to the UK is under 6 hrs, the extra room/comfort is lovely. I didn't book our return seats before leaving because I wanted to see if it was worth it, but I booked the preferred seats for our flight back. I figure in the grand scheme of the plane ticket/vacation price, what's a little more. And I'm old (and achy) enough now I'd rather the comfort.
So if you are flying AC and are wondering about preferred seating, for us, it was worth it.