I have the Dell 2407WFP-HC on an ATI Radeon HD 2600 Pro graphics card, and I think the monitor is just great. Shadows, highlights, and video gamma are spot-on, no calibration required. The colour gamut almost matches Adobe RGB; it is significantly wider than sRGB ... I think the current Dell xx09WFP series monitors have gamuts that even exceed Adobe RGB.
It wouldn't make sense to hardware-calibrate the Dell 2407WFP-HC because (1) it is well-calibrated right out of the box, and (2) it doesn't incorporate 10-bit or 12-bit look-up tables so any attempt to change hardware settings would only deteriorate image quality (i. e. would cause banding and/or uneven tonality). Generally, hardware calibration is needed only when you must match one monitor to another precisely---which rarely is the case in real life. Even when you actually are using two monitors, only one will be used to do colour-critical work; the other will display tool palettes and other non-critical stuff. So normally profiling the monitors properly is all that's required.
Please understand that hardware calibration inevitably means a deliberate restriction of the monitor's native gamut and dynamic range. Matching two monitors effectively means to reduce both to their common denominator, i. e. to the intersection of their gamuts and ranges. So unless desperately required, any kind of calibration is to be avoided in order to take advantage of the monitor's full gamut and dynamic range.
So don't worry too much about the monitor's aptitude to get hardware-calibrated. The NEC 2690 does have three 12-bit look-up tables; the Dell 2709WFP does not. So the NEC can be hardware-calibrated without loss of image quality; the Dell cannot. But the point is: the Dell does not need it, just make sure it's properly profiled.