It really all depends. I have owned two Compaq/HP laptops which were awesome; the Compaq kept ticking for four years until the HD became corrupted/died. Actually the battery went bad first after two years (and I eBayed a replacement), the DVD drive failed after three, and then finally it wouldn't boot anymore. The HP laptop is great despite being under-powered and running Vista. So the HP/Compaq consumer laptops are pretty good, and they are generally sanely priced too. I have been using a Dell Latitude notebook at work for two years without any problems, and I would buy one of those off of Dell['s small business website in a heartbeat. Others I know have not had such a great experience with Dell laptops and they have less than stellar opinions of Dell. My partner uses a Dell notebook at work, and he's gone through three of them since I've known him. Since two of them were the same model as my work laptop, I was surprised he was having so many problems. I occasionally use my partner's spare Dell notebook at home, and it works well. Its not incredibly powerful, but it boots well, runs MS Office and Chrome, and I can't really complain.
It's because the Latitude is a business laptop. Dell actually gives a shit about those guys. Seriously, though, we had a latitude back in the repair area that was ancient, and you couldn't kill it!
I bought an HP DV7-6163 about two months ago after reading reviews and talking to a friend who runs their own computer repair business. Awesome machine.