Yes, in my opinion at least, Dell makes a pretty reliable laptop. I haven't heard anything bad about the XPS series in this regard either, so if it is reliability you're worrying about, I'd say go for it. What else do you need know?
Dell is a strong contender when it comes to laptops. Above average quality and very strong pricing. Two points from me:
1. One place you might look for very detailed laptop information is notebookcheck.net. Its European, but most models are worldwide and they review in very high detail. They also provide some performance benchmarks, etc.
2. This study was posted on Tom's last fall. While it is definitely not a perfect report, I think it does provide a general representation that might be helpful.