I currently own and use three Dell laptops, one HP, one Lenovo and one Toshiba. Over the past few years I have also owned and used one more HP, one Compaq, one Gateway and three or four more Dells - these are now retired and gifted to friends or family. (Yeah, I work in IT ;-)
I purchased all of the Dells from the Dell outlet store, so they're refurbished or "scratch and dent" or the like. This generally means a much lower cost and much quicker delivery, since you're buying a machine that already exists instead of having one built just for you. The only problems I've had with any of the Dells is the cooling fan on an Inspiron 9400 and the power brick on an Inspiron 9100 (both now retired) that died after a few years use. Both were easily replaced (by me, out of warranty) and I never had any other problems.
The one laptop with which I've had consistent and ongoing problems is the Toshiba - a Portege M400 tablet. I paid more for this machine than for any other two of my laptops combined, including paying an extra load for the "no matter what goes wrong we'll have someone onsite in 24 hours to fix or repair it" warranty service. This machine has been plagued with problems, and Toshiba's warranty is so full of loopholes that each time there is a problem it takes me weeks to convince them that the problem is real, and then they ALWAYS say that this type of problem falls outside the terms of the warranty, and that I need to ship the computer to them for diagnostics.
So based on my personal experience, it looks like any vendor can give you a lemon, and at that point you have to hope that their service department doesn't suck too hard. I would not hesitate to buy another Dell for myself or a family member, but I will NEVER buy a Toshiba again, ever.