I've been on ZA, AB and ZC in first class between Toronto and London and they're fine. (I think there is no crew rest space which is where the extra seats come from. Off thread, but I find first far inferior when served by mixed fleet. They just lack the personal touch and experience that long haul staff provide. So much so, I've stopped booking first (on avois on the route (excluding this winter where there has been on first) as the service was so bad on my last two flights. I like the 777 for first trips as the cabin has space. (I do miss 1A / 2A on the 747.