Pabs said:
as far as I can see, if they look good I'm not fussed! I suspect they are made just as good as the real thing? Not like they can be made by a 5yr old with a chisel is it...
Unfortunately not...
One alloy is not as good as another, if the quality of the alloy or the casting process is poor then several issues can arise.
The wheel may simply not be as strong as others, this means that over time (and particularly over pot-holes

) the rim can warp, sometimes quite badly.
The wheel may be 'overbuilt' to compensate for the metals inherant weakness - this'll make them rather heavy.
The alloy may be porous, therefore the air from the tyre can slowly leak out through the metal.
These problems aren't exlcusive to replicas, as if you look on the TT forum - owners were complaining about 18" Audi rims buckling, some people got warranty replacements but others didn't.
Having fitted extremely heavy TSW Pace rims to my old civic, and feeling first hand how bloated rims can affect acceleration and handling, plus knowing the problems that can arise from shoddy build quality i'd stick to OE or recommended wheels from quality manufactures eg OZ, Kei Racing, Compomotive.