Any perception that Dell U-Series monitors are not up to scratch is garbage.
I think it's sort of the other way around.
@ Both of you, I think you're both right. But they're different market segments.
Look at it this way.
I have a 7D, a 15-85, one L-lens. I'm making photos for my own enjoyment, but I want those phtos to be as good as possible, within the realms of of what I can justify as affordable, weighed against all other factors, like wages, rent, and food bills.
I do not have a 1D/s, 5D, 70-200 f/2.8L, 50/1.2, 85/1.2, MP-E 65, TS-E 24, or any of those other wonderful lenses I drool over too much. I'm not making billboards, nor books. I'm not selling to a customer who will pulp a run of 1000 books becaue the colours were "only 99% correct".
I am the definition of 'Prosumer'.
Basically, the Dell Ultrasharp are the 'Prosumer' monitors. I was thinking of an analogy with the niftyfifty, but maybe the Samyang 35/1.4 is more appropriate. Either way, under the right conditions, and using it properly, they're damn good lenses. They may not have that final 1 or 2% to be "the best", but then you're paying Zeiss money. For the price, even for double or triple the price, you can't do any better.
The $570 I paid for my 27" Dell is prosumer money. It's about as much as I paid for the rest of my new PC. The cheapest Eizo I've seen is
€700, over $1000. For a comparable size/res, it's
€1500, $2000, now we're at 4x what I paid.
I can't comment on the Apple monitors, nor colour shifts on my dell as it's less that 6 months old. But it's "good enough" for me, and always will be. There's no scenario I can imagine in which a $2000 eizo monitor would be justified for my usage. For some people they can accept no less, because affording tomorrow's dinner depends on it. That's the difference between Prosumer and Professional.
(Stringfellow above sounds like the definition of 'professional', or at least sounds like it talking about 'selling more')
In short, if your income depends on accuracy, get an Eizo. If you like playing around like me, get a Dell. Or for somewhere in between, get any IPS-panel and a calibration kit as long as you can install the software (afaik there's no calibration software for linux readily-available, hence I got the pre-calibrated dell).
(and no, i haven't thought about the HP or NEC IPS panels for this comaprison...)