http://www.tftcentral.co.uk/The single very best source of unbiased monitor reviews. You cannot get more in-depth and professional than this :- )
Eizo is just a brand. Nowadays they have full price range, which vary in features and quality. Simply buying 'Eizo' (or NEC) doesn't mean you get better quality than simply going with Dell. Eizo has bunch of 27" monitors, ranging from basic IPS 8bit sRGB panels, to high-end 10bit WideGamut panels, with lot of other special versions, like fast-latency game oriented Foris models.
So you choose the kind of features you want (color depth, color gamut, SW/HW calibration, contrast range,etc..) then some budget and then you can compare exact models from different brands.
But generally speaking, with the high quality of mainstream displays, unless you're extremely picky colorist, buying top-end NEC/Eizo is wasting your money. You really need to know why you would need them , otherwise you get very little benefit compared to better priced counterparts. High-end Dell monitors are extremely popular and well received in professional reviews above.