I'm all for Superarticulation but if theres one area where the compromise on the sculpt (and paint) is just too great its the head. Please, no more.
The case against:
-Balljoint necks ruin the jawline of figures
-They spoil the hairline's of figures (typically hair must be cut short)
-They sometimes spoil paintwork (usually where hair is painted over with skin tones instead of brown etc)
-They sometimes don't even do what they're supposed to
-You can actually lose the head of a figure
The case for:
-Highly effective on some figures for creating scene accurate poses (but primarily figures who also have helmets or whose heads are helmets)
When Balljoints attack!!!!:
Saga padme Lars Homestead - Honestly did this figure need a balljointed neck? What dynamic poses did Padme strike whilst in this particular outfit. In this case the jawline isn't affected in a huge way, however on my figure's right hand side she looks like she's developing some kind of tumour at the base of her skull, or at least losing hair in that area. It could be a case of poor paint app. or it could be a lumpy bit of sculpting as a result of the ball-jointed neck.
Saga Admiral Ozzel - this figure is blighted with really obvious lines from every angle and a neck which appears too long in relation to the straightness of his shoulders. And his hair looks like its receding from the back - it doesn't reach down the back of his neck like a normal person/figure, instead it abruptly stops level with his ears. Thats not natural and its a compromise made as a result of the ball-jointed neck.
Evolutions Anakin (AOTC&ROTS) - the AOTC figure has no jaw. Again, really obvious lines from every angle but the front that detract from an otherwise fine sculpt. And CRIMINALLY the balljoints don't even work. Even with the sculpting compromises the movement offered is minimal at best and is therefore not worthwhile.
VOTC Leia - long neck syndrome
TSC Leia Boushh - no neck syndrome, again minimal movement possible so why bother?
VOTC Han - a long neck which leans oddly far forward, and his hair is too short at the back - necessitated for the added movement but sacrifices film accuracy
When Balljoints go right:
Any figure whose head is a helmet, including VOTC Boba Fett, the SA Clone wars Clone and the recent TSC AT-AT driver. Also the occasional removeable helmet figure such as Saga Lando in Skiff guard outfit.