Regarding the heat, on my visit to the beautiful national mosque there, it was about 115 F. The trick is to wear a lot of clothing so that you'll be insulated from the heat. It's about 20 minutes from the Etihad Towers hotel with the excellent Rosewood buffet.

My food experience on Etihad in F has always been over the top, on 777 or 380. There may be slightly fewer options on the menu, but the chefs can often come up with all kinds of creations, including baking personal cakes on board, if they're not too busy.

On Emirates, the F food is apparently the same as in J, just on better plates. On Qatar, same deal, sort of mediocre food in F.