Ok the Yellow car above is in fact a S4 with the two outer grills modified and the middle bar removed (I can get you a write-up to do this). So if you like the yellow car you will need to hunt around for a S4 front bumper and sides and if you want to be different get rid of the upper door trims like the RS4 and then fit a Euro spec S4 rear bumper.
I have to say the rear bumper is not cheap but the rest of the parts you can pick up quite cheap-ish second-hand.
The advantage of this is that the parts are all Audi.
The advantage of plastic is that it bends unlike fibreglass which is less forgiving and tends to shatter if hit.
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