having a cup we dont have xenons, the rs interior or steering wheel insert, auto lights/wipers, and factory suspension was different i believe. I think thats is all mate.
Plus; a lower power headunit, cheaper speakers? no Alcantara door cards, I think the finish of the centre console is shiny rather than soft touch, cheaper gear knob, no rear grab handles, non heat reflective windscreen, no engine cover, removal of some sound deadening, no headlamp washers, no climate - only aircon, cup badge on doors, single bench seat with no headrests. Cup suspension pack (option on normal 182) with updated and lowered shocks which are not interchangeable with standard car due to different bolt spacing, stiffer and lower springs. Different front hubs. Also had larger rear spoiler and front splitter (again options on normal 182s).
BUT 182s are about driving and all the above doesn't really bother me, luckily mine had Recaro Trendlines