“F-18/15-ski?”
Essentially, yeah. The SU-35 is the latest evolution of the SU-27 Flanker, which was basically the Soviet Union’s answer to the F-15 (with the concurrent and cheaper MiG-29 being more or less their counterpart to the F-16). Probably the best fighter platform the Russians have fielded to date. The ‘35 model is supposed to be very, very capable (4++ generation)- supercruise capability, thrust vectoring, etc.