Funny thing about Dell: their business stuff is actually pretty good. It's not at all like the commercial/consumer-end stuff. I have no idea why it's so different. I suppose it has something to do with selling in bulk.
They're extremely hard to find, of course. But if you know people...
I actually got a small (slightly used) box for $200 that has about the same specs as the Alienware. The chip is only an i3, but it's pretty fast and the video is only 1mb of DDR3. (It's a dedicated card, even.) But it's still more than enough for what I use if for.
I've got it set up as and HTPC.
It's standard cubicle fare, so it's very plain looking, but it's very well built. The form factor is small. It fits on my TV stand. I drilled some holes in the chassis for some extra cooling, but you can't seem them. The hard drive was only 500. I eventually replaced it with a terabyte. And put in a PCIE remote receiver.
The total cost was still under $300. I've had it for over a year now, running almost constantly, and haven't had any problems.
There's no way I could find something this good (especially for the price) at a big box--and certainly not from Dell.
I have a business laptop from them also. (Got it from the same place.) It's older, but built like a shit brick house. I've dropped the thing a few times. It's fully modular and really easy to take apart to clean and upgrade. It also doesn't have those annoying extra "media" function buttons that seem to inevitably short the mobo.
I've compared it to the commercial Dell laptop--Inspiration or whatever it is--it felt like a toy compared to mine.
Really don't know why there's such a discrepancy in build quality.