Alfredo wants to upgrade his Windows laptop to a workstation laptop or a desktop. Leo says he'll have to decide between maximum portability or maximum power. It's not just that the price of a workstation laptop would be higher, but it's also the weight, screen size, and battery life that would factor into the decision. If he chooses portability, then he's going to sacrifice some processor power, it would have a smaller screen size, but the battery life would be far better.
Leo likes Dell because he could spec out what he wants. Hard drives depend on how large the data files are that he'll work with. Lenovo is another good option. An SSD would give him great performance and fast boot up times. He may want to upgrade to Windows Pro with NVidia Quadro graphics and 8-16GB of RAM, depending on his budget. He'll also want to make sure he gets a Haswell processor.