How can 24 (or more likely 48) SU-35S be useless? I can think of several Chinese fighter regiments – close to 40, in fact – that would be exceedingly happy to lay their hands on 24 SU-25S!
No one would dispute that SU-35S is a fine fighter, superior to anything in PLAAF’s inventory. About compatibility and avionics, what would the problem with fitting Chinese avionics, if that is what they prefer? As far as I know, Russia has had no compunction about putting French and Israeli avionics into export SU-30’s, especially SU-30MKI for India.
Have we ever seen China buying anything they did not think they needed? With J-11B being produced at snail’s pace, PLAAF’s equipment plans must have been thoroughly upset.
doesn't china already have the biggest fleet of flankers outside of Russia? they are making like 5 different versions of flankers themselves so why would they be thoroughly upset if production is slow right now. they weren't desperate for planes like they were two decades ago. china's current fleet of flankers, j-10's, jh-7A's and j-8's is a decent fleet for defense. i'm not saying the SU-35S is a bad plane or they shouldn't buy it but why would they want to spend those funds for an import when they're domestic programs are blooming with two stealth fighters in testing phase. there is a wing type subsonic bomber that we don't know much about then now we just got pictures of a model that looks like a high speed stealth bomber which may or may not be program in progress. point is they got plenty of better projects to spend their money on than the SU-35S which the Russian airforce hasn't even bought themselves or if they have, in tiny insignificant numbers.