I would choose the ARN/CPH old 744 over the A345 (when it comes to premium economy). Service in Y+ is about the same as C on other routes when it comes to service (at least on ARN/CPH-BKK). Pre-dep drinks, pre-dinner drinks with pre-dinner snacks, 3-course meal with 4 choices for main course, cheese tray... sandwiches, snacks and drinks available between meals. Second meal service before landing has 2 main courses to choose from.
Amenity kits are not as good as on Royal Silk routes.