[Pyramid] Cutting-Edge Armor Design: Trauma Plates
 

In High-Tech, trauma plate for TL8 Fragmentation Vest provides DR 25, weights 16 lbs, and costs $300
Using Pyramid's design rules, you can get similar value by using Improved Ceramic on Chest location: DR 25 and 15.75 lbs. However, the cost is way off: $7,875! I can only get anything close to $300 by ignoring CC and using TL9 cost.
Did I miss something?

On similar note, the trauma plate for Assault Vest and those from the box on p.67 seems too light, you'd need ultra-tech materials to get anything as light.

Re: [Pyramid] Cutting-Edge Armor Design: Trauma Plates
 

Some of the discrepancy is because High Tech uses the real world cost and weight of trauma plates but claims that they cover the entire chest instead of just the vitals.

Re: [Pyramid] Cutting-Edge Armor Design: Trauma Plates
 

A trauma plate(or a standalone ballistic plate) covers normally less than a square foot/side.

As example my SAPI style class IV plate is about 25cm by 30cm size, with missing corners for even less area.

But the pyramid design rules give a 5.25 square feet for chest location, but the actual plate is about 1.5-1.6 square feet total for a set of front+back plates.

So as DanHoward says, the actual covered area by such is much smaller than indicated in High Tech.