ST1 features include:
Unique 18" ST alloy wheels
Unique ST design full bodykit
Unique ST rear spoiler
Dark smoke-tinted LED rear lights
Black finished roof rails (estate only)
Recaro sport front seats with fabric trim
Radio/CD with SYNC in-car connectivity, voice cobtrol system, DAB, AUX input and USB
Ford Power Starter Button
Unique ST leather gear knob
ST front door scuff plates
Torque Vectoring Control
Deflation Detection System
Thatcham Category 1 Alarm
ST2 Features, additional to ST1:
Recaro sports front seats with partial leather trim
Sony radio/CD with 4.2" display, SYNC in-car connectivity, Voice Control System, DAB, AUX input, USB
Dual-zone Electronic Automatic Temperature Control (DEATC)
Heated windscreen
Automatic headlights
Auto-dimming rear-view mirror with autowipers
Unique ST floor mats front and rear
ST3 features, additional to ST2
Bi-Xenon headlights with jetwash
Recaro heated front sports seats with full leather trim
Drivers and passengers 8-way power-adjustable seats
Recaro Sculpted 3-seater rear bench seat.
Copied that from a ford forum, was looking into them myself for my brother.