PFs = 1/4 scale. That's it. It can be a fully sculpted piece and still be a PF. It can also have mixed media elements too.
A MAQ can be anything. Movie based, comic based, any scale, a diorama, mixed media, fully sculpted, or any interpretation of a character. Almost always, a 1/4 MAQ comes with a higher price tag than a PF.
COM = 1/5 scale comic based statue. It used to mean fully sculpted but it looks like sideshow is now using mixed media on their 1/5 statues too (see Avengers Assemble Thor). I honestly don't know if they are even making COMs anymore. Recently, sideshow has labeled their 1/5 pieces as just statues and not COMs. The term COM may possibly be a thing of the past. I can't even remember the last statue that sideshow released with a COM label actually on it. Also, old COMs were both 1/5 and 1/4 scale pieces. However, after the Rhino COM (it was the last 1/4 COM released), all COMs were reclassified by sideshow as being 1/5 scale fully sculpted comic based statues. I may have missed some things but that's pretty much the gist of it.
