I found these guys on kijiji and they were pretty much the only place i could find selling replica bmw rims. I did a fair bit of research online before hand trying to determine if the replicas would be more prone to cracking or if they would be off-round, but real world examples of problems were rare although you inevitably get people who say the real BMW one's are much higher quality.
The rims were carefully wrapped and boxed and I was able to look up the model number online which led me to a chinese manufacturer site where they indicated these are low pressure casted which is exactly the same construction method as most OEM wheels. Aesthetically perfect, and they mounted with the same amount of counter weights as my factory rims when the tires were installed.
I paid for a full set of 4 rims what a single BMW factory rim would have cost and after driving for several months on them I would recommend them in a heartbeat. Great prices and a nice showroom and good sized warehouse.