If you review these forums, you'll find just about all makers have problems, some more than others at times or for certain models, yada, yada. The point being, it doesn't matter about the end product but rather how the warranty and/or support service makes a problem/trouble system become working again. In the case for Dell and HP, both don't measure-up to past history. They both fall down on after sale service. However, IMHO Dell is the better of th two. At the same time, I truly believe the "self-help" from their support websites are very good, its the actual people support you count on that differs from one maker to another. Everyone has a "horror story" its the number of real horrors make differ one from the other. I do suggest if possible buy the "business model#" to help lessen problems as they *maybe* more robust and capable. Further, the support could be just as worthy of the sale.
If you like, check out other vendors that make 3rd party PC's which are fact nothing more than "generic PCs" build by local or online vendors. In many cases these offer the h/w side are as good as any other OEM type system. Further, they usually can be more customized PCs, but again look at what your getting plus read the fine print on any purchase. No matter where you get the system, keep the paperwork and if support is required maintain a log.