I'm actually looking at those exact wheels for my 240 but in bronze...light, decent looking having only one bolt pattern, the right widths, and best of all....cheap. I'll probably buy two sets of rear wheels to keep a good supply of mounted tires.
Anyway, the 43 offset is a bit too high, and the face of the wheel will sit too far inside the wheel housing, possibly causing rubbing on suspension components at full steering lock or suspension extension. A spacer will push the face of the wheel closer to the edge of the body.
Is that the lowest offset for that width? I'm looking at 18 x 9 at something like a 17mm offset. The same size wheel can be had in the same 43mm offset as above, or the lower. Not sure if the same holds true for the smaller diameter and lesser widths.