I have used Dell on and off for 15 years including 1000 unit rollouts.
The mob I am working with now is rolling out more than 1000 dell PC's!!. Probably closer to 10000!.
I have a dell server for my business, its been happily chugging along for 6 years now without any incidents. All our desktop PC's are dell and a few laptops (we are not a big company). We also had Sony early on, but the later ones were crap. Got a mix of laptops now, Sony, Dell, Mac, Asus. Only faulty laptops I have here are sony and toshiba.