Heller/Airfix WRC kits are fine for quick 'shelfers'.
Here's the Impreza....(Seems to me I don't have a FINISHED pic of this car )
I have not built an Airfix/Heller Focus yet, but seems similar. Woefully incorrect interior/chassis, but an OK shelfer.
Airfix/Heller is the only game in town for the Citroen Xsara as well.
Use the Revell Focus for some parts with the Tamiya Focus for more correctness.