I took my Hong Kong Airlines flight and I thought that I would write my experience.
I booked two J seats for my husband and I, YVR to HKG. 100,000 points and around $67 each.
I used their WhatsApp to select my seats. We were supposed to be flying their newer layout that they use for this route with this seat configuration:

I got an email about a week before the flight saying that my seats had been reallocated and that it would now be their old configuration:

I went back onto their WhatsApp and confirmed our seat selection again with staff.
On the day of the flight, we checked in and our seat allocation had changed; I was now supposed to be in a honeymoon seat config with a stranger. The staff said nothing could be done about it.
On entering the flight I spoke to their airline stewardess who proactivley spoke to my seatmate and moved them, so my husband and I could sit together:

The food wasnt very good, the IFE was pretty awful (not even a flight map and only about 8 english movies) but the staff were amazing. The seat was comfortable and we got some great sleep. Very VERY dated product. They wouldnt let us que for the bathroom which caused a range of issues (they gave you a number then came and got you when it was your turn to go to the bathroom, but it was chaos really).
My husband wont fly them again as the plane was very old and hes a super nervous flyer that percieves old cabins as unsafe.