This is when molten aluminum is simply poured into a mold and allowed to cool off. This method results in a wheel that has lesser density aluminum, since no pressure is applied (most factory wheels use a what's called low-pressure casting method). What this really means is that the replica wheels are much more likely to get bent or cracked, since they are made from much weaker, more porous material. We have seen this happen over and over again. 

When a replica wheel is made, it's made by copying the design of the original wheel by creating another mold. There are always differences since a wheel mold is very expensive to make properly ($25,000+). You will notice slight differences on the front and major differences on the back. All of this is not only because the wheel mold is made in the cheapest way possible, but also because it's virtually impossible to copy the design of the original mold without having super expensive equipment. Furthermore, if a wheel is made the same as the original, the manufacturer runs the risk of being sued. This recently happened with BMW issuing cease and desist letters to manufacturers, so you'll hardly find anymore BMW replica wheels for sale on eBay. 

For example, do you think Toyota is going to allow a factory that makes wheels for them also make the same wheels for someone else? Wheel manufacturer making millions of wheels a year for a car manufacturer will not risk their business for a small company making wheels in the hundreds or maybe thousands. Not only that, but they also face the risk of being sued by the manufacturer who owns the rights to the design of that wheel. 

They also go through what is called a salt spray test and many other tests to make sure the finish will stand up to road salts, chemicals, and other elements. All of these tests are extremely expensive, and virtually no replica wheel manufacturer does any of them. The finish on replica wheels is usually of the cheapest design, with no testing done whatsoever so they can be made as cheaply as possible. 

We have seen many replica wheels that are out of round right out of the box. They cause a major vibration on the vehicle or rub on suspension or brake parts since no fitment testing was done before they were made. This does not even address the issue of replica wheels causing a vibration from getting bent, as mentioned above.