Alai: I'm wary because people have commented with reports of bugs on the UFO series. And the first game (Aftershock?), I think still has SecuROM. And I am still unsure of compatability with Vista 64. Otherwise, I would buy it immediately from Amazon (since Steam and D2D doesn't have the trilogy, only Afterlight).
illegalyouth: just to clarify, in the discussion fenixp linked, i
found that aftershock (second in the series) has starforce; although, if purchased through gamer's gate, it does not. the other two games, aftermath (first game) and afterlight (third game), do have secuROM.
Unless Gamer's Gate installed the Starforce themselves, Afterlight shouldn't have Starforce.