I was on the CX 827 from YYZ to HK on Y recently. It seemed to me that the seat pitch is narrower than that of A340-300 and A330-300.

It was great to fly direct to HK from YYZ but I doubt I would want to do it again on Y in the 340-600. I am 1.69 metres and found that my knees touch the back of the seat. 16 hours was way too long to endure such limited room.