My last 2 work laptops have been Lenovos. Before that strictly Dell - I still use my 9 year old Dell Lattitude D630 - still fast - has dual core 3+GHz 64-bit processor, 4GB ram, 360GB disc, Wifi, bluetooth, HD display. My current laptop is a Lenovo Carbon x1 - nice, good features, light as a feather, great battery life. It has a dual core 3GHz i7 processor, 8GB ram, 250GB SSD, Wifi, bluetooth, and can drive 3 displays - the laptop screen and two 1920x1200 HD external displays. Both have 1Gbps ethernet connectors, though the Lenovo also has a USB 3.0 port - the Dell is limited to USB 2.0. The Dell has an eSata port. The Lenovo doesn't. Both have good audio, microphone, video camera. Being 9 years old, the Dell has held up, both physically and feature-wise, to current laptops.
I know a lot of people who use HP laptops. Most really don't like them much, and I think they don't hold up as well as Dell and Lenovo units, although my grandson has an HP laptop/tablet that my attorney (and good friend) gave him which he uses for circuit design and commercial art work. He runs Windows 7 on it. The tablet features (stylus for drawing) are good for his design work. So far, it is holding up ok, though since he is a computer hardware wizard, he is capable of fixing it down to the circuit level. Even has his own reflow solder station!