We just got back from our trip and here is our ranking for J class.

1. Qsuites (but only because the HDMI connection allowed me to connect my Switch and play video games on the screen. I know, I am so mature...) The double bed was a neat novelty, but it wore off quickly when we realized there was zero air circulation with the suite doors closed.
2. A380 (if this had an HDMI connection it would be #1 )
3. 777 in 2+2+2 config
4. LATAM leased A350. We were actually very pleasantly surprised by how roomy and comfortable it was. I would definitely fly this again. The only reason the 777 was higher on our list was due to the seats being a bit wider.

Honestly, it does not matter which hard product you fly with Qatar because we had wonderful experiences due to the crews. We did wish we had longer layovers in DOH to explore the lounge and airport. I would not hesitate to fly them again, but I am not going to go out of my way to fly with them. Meaning, I'll seriously consider jumping on future great deals.