Think you got it wrong
the cheaper option is single piece Ali, Glass/carbon and Magnesium are generally more expensive options and as usual touch screens are much stronger/resilient
More than just software
White hot: Inspired by runway trends, the rose gold and frost versions of the new XPS 13 debut an authentic arctic white woven glass fiber palm rest developed specifically for Dell. Our design team worked tirelessly to get the details just right—carefully crafted backlighting, UV- and stain-resistant coating to prevent yellowing and staining, and coordinated packaging and accessories.
Stunning strength: The XPS 13 is cut from a single block of aluminum, so it’s more durable than a machine that’s pieced together. Carbon fiber, inspired by the aerospace industry, and woven glass fiber of the palm rest, allow for maximum strength and minimal weight. Corning® Gorilla® Glass 4 is twice as damage resistant compared to competitive products.