Having muscular configurations like this is pretty common in the world of workstations. However, having a 15” laptop with this kind of power in a 4.92Lbs (5.47Lbs for touch version) sounds very nice. The touch version is noticeably heavier, which was common to all touch laptops just a few years ago, but recent computers such as the Yoga 3 have proven that it is possible to build an ultra-light touch laptop. Typically, Workstation screens have better color output, brightness consistency and calibration abilities.
More importantly, the workstation is certified for a number of CAD applications, which is really why one should pay for a Workstation instead of just buying a robust consumer laptop. The idea is to remove as many potential IT issues as possible, because each hour of downtime can potentially cost a lot of money in terms of engineering or design productivity.
There is the overall robustness of the laptop (when compared to a consumer counterpart): although Lenovo is still going through the mil-spec (military-level robustness) certification, but the company is aiming to officially offer this level of endurance by the time the product hits the market. This should be more than enough to cater to most engineers needs in the field… Other details like the full-size numeric pad, or the Bridge battery system (there are two batteries, so you can change one, without downtime) make this a pretty solid workhorse.