At the risk of joining a debate I'm not hugely interested in I might as well just say that the cinematography was probably one of the real stand out elements in Alien3. Due to advances in latex I'd say the suit is better constructed (materials wise) and that generally the glimpses you get of it don't reveal the fact that the guy wearing it is too plump to match the puppet, but that's the art of movie making. Yes, the biomechanics have been softened to the detriment of the design but a big improvement over it's predecessor IMO is the return of the dome.
Despite the differences, I still prefer the Alien3 as it appears in the film over those in Aliens. The big issue being the head and the hands. The 3 suit doesn't look good in behind the scenes shots really, when he's walking to set etc the upright pose is lessened hugely by the lack of back tubes, but in the film itself the biggest issue is the compositing of the puppet.
I'd agree that the airbrushing in the production line looks nice, but the chances of any of that being seen in the film, with the light levels and slime are practically zero. The details really need to be sculpted into the suit to be seen once lit for filming.
