The following is quoted directly from Geotroid:
I have seen three of them on eBay and all came from Italy (ebay.it). The first time I saw them, around 2008, a seller posted two separate auctions for two separate black Questars that ended minutes apart. I won both. Each figure was play-worn, and I sent the better looking one to [another collector.] He agreed – they are authentic. The play-wear worked to our benefit, because there are visible sports were the paint chipped off revealing raw, gray die-cast metal underneath. This is important, as it shows the black paint was NOT applied over a gold anodized (Questar) or orange painted (Roton) torso.
One aside – I also saw a loose orange Questar for sale in Belgium. Obviosuly, it was Questar head on a Roton body. I didn’t bid as it was a bit high (Somebody else did bid and win it, though) but it made me chuckle. Was it a difficult customized head-swap or was it sloppy assembly at the Hong Kong factory?
Here are his photos: