"I could say that the Su-34 is "more advanced" because of its range, avionics, ground-strike capabilities etc. If you want to know which a/c is the most manouverable, for example, say that. State the qualities you are looking for."
I could also say that mig-25 is the best fighter because it is fastest a/c.
So MR LY something when you compare two or more aircraft you must luck about all [or almost all] aspects you have data about. Strike flanker has a greater range and most advanced strike capabilities but what about a dogfight or stealthiness,takeoff/landoff distance etc.