If there was not such a discrepancy between proto and production (especially with SSC) a NRD wouldn't have been necessary. They've done it to "stop people cancelling" but most people cancel because in-hand pics show up and show that it's fallen short of the proto.
Can someone show me where this cancellation policy is shown on Alter Ego's actual product order page? Nowhere on the page do I see mention of it, even when you click on "Pre Order Policy."
I don't own any 1/6 Vaders and I only have one (bought loose/used) HT figure, so I'm not really in either "fan" court (SSC or HT) here, but the Sideshow DX Vader has a quite noticeable sculpt issue with the facemask, and the dome is proportionately too small. To me it's not subtle. The mouth triangle is far too wide and large and the nose too small and the cheeks are noticeably too "flat" across. The higher the contrast lighting, the better the figure looks, but it's pretty clear. I've handled the fig and it is an awesome quality piece but the facemask just doesn't look very screen accurate to me.
The HT Vader prototype, while definitely not 100% (and obviously more a "all film" Vader than ANH specifcally) just looks way closer to me facemask sculpt-wise. Sure, the dome is slightly off and should be lowered, but to me this facemask looks a whole lot more accurate than either SSC offering.
ESB prop helmet on left, HT Vader on right (very different lenses, so slightly different angles)