High quality for their time. The toilet bowl was very heavy for its screen size, and had minimal volume for battery. The G3 iBook lacked rigidity, and had a tendency to damage the mainboard if picked up from a corner. The G4 iBook had grounding issues, and would occasionally get spicy with two-prong outlets. All three of these issues were directly related to the plastic chassis. All three were great laptops for their day; none would be acceptable in this decade.

There’s nothing wrong with plastic as a material, but there’s a lot wrong with many of the designs of mid-tier laptops that happen to use plastic. The plastic isn’t as much a cause of their problems as it is a signature feature of all hastily assembled corner-cut devices.