Just saw this thread now, been collecting the diecast versions of Skylines for a while now. Have the three Bathurst R32s in 1/43 scale along with a gunmetal grey GT-R and Calsonic R32.
In the 1/18th scale I have the Autoart Gunmetal R32 and R34 Z Tune, Calsonic, Hyoseki, STP/Taisan, Axia R32 Group A Touring Cars and Pennzoil R34 JGTC car.
May be selling the Axia and STP cars soon as I have two of them. Need to get the Bathurst 1991 car and a couple of other Group A Jap Touring Cars in the 1/18 scale.
In plastic kits I have the Axia R32 Touring Car and the Pennzoil R34 JGTC car (still sealed), also in the middle of converting a Calsonic R32 kit into one of the Winfield GT-Rs as I came across a decal kit to suit 1/24 scale.
Collection is nothing special compared to others, but its getting there.