As expected, both models are rolling into Australia with a significant number of upgrades, moving the twins on neatly since their 2014 Australian launch and 2015 equipment update. A new spec.R model has also been added at the top of the range.
Styling changes to the "heavily revised" pair include a revised grille and front bumper, along with new 19- and 18-inch wheels. New steering-responsive LED headlights with integrated indicators also feature, as do new LED fog lights.
All models get those new headlights and LED foggies, along with a new higher-resolution 5.9-inch instrument display ('Multi-Function Display') to replace the 4.3-inch unit that preceded it.
Subaru says the entire WRX and WRX STI range also benefits from upgraded interior quality, with "a more cohesive interior finish".
There are more gloss black surfaces in the STI, too, including the door switch panel, instrument panel centre, gear-shift surround panel and the steering centre bezel.
New equipment upgrades for the WRX models includes revised suspension, with changes front and rear to the damping force of the struts and to the spring constant of the coils, while the rear also gets stronger stabilisers.
There's also Jurid performance brake pads - promising a 20 per cent improvement in braking efficiency - and red-painted callipers, new 18-inch alloys, heated door mirrors and electric lumbar support.
EyeSight Driver Assist, electric parking brake and Automatic Vehicle Hold also feature, but only for models equipped with the CVT automatic transmission.
Automatic headlights and wipers also feature, trickling down from the WRX Premium spec.
For the 2018 model year, WRX Premium now adds eight-way powered driver's seat with dual memory and electric lumbar support, along with heated seating for driver and passenger both.
Upgrading to the WRX STI adds Brembo six-piston brake callipers up front and Brembo two-piston grabbers at the rear, all painted yellow. Cross-drilled rotors also feature in STI models. Red seat belts feature in the cabin.
Also unique to the STI are 19-inch alloy wheels, standard for the first time, along with revised suspension promising "optimised roll rigidity, suspension coils and shock absorbers, for both excellent control, stability, and flat ride comfort". We'll put this to the test soon.
WRX STI Premium and WRX STI spec.R also add the Front View Camera. Both get an eight-way powered driver's seat, but the spec.R upgrades the front seats to a more supportive Recaro design.
The powertrain in both cars is unchanged, with the WRX driven by a 197kW/350Nm turbo four-cylinder boxer, while the STI gets a 221kW/407Nm 2.5-litre turbo boxer.
2018 Subaru WRX and WRX STI pricing
(Excludes on-road costs)
WRX manual - $39,240
WRX Lineartronic CVT - $42,240
WRX Premium manual - $45,640
WRX Premium Lineartronic CVT - $48,840
WRX STI - $50,890
WRX STI with rear spoiler - $51,190
WRX STI Premium - $55,640
WRX STI Premium with rear spoiler - $55,940
WRX STI spec.R - $57,690