Complex sentence: The Tu-204SM benefits from a compact airframe and enjoys upgraded PS-90A2 engines (ETOPS 180 rated), while enjoying many design and aerodynamic similarities to the PS-90A-engined Tu-204-100/100E/100V.
Split into simpler sentences: The Tu-204SM will benefit from a compact airframe and will feature upgraded PS-90A2 engines (ETOPS 180 rated). However the Tu-204SM will feature many design and aerodynamic similarities to the PS-90A-engined Tu-204-100/100E/100V.