The HP Z24i IPS provides an astonishing amount for a really reasonable price. The picture is top and is not very good the iMac display to suit and also not reflected. The colors were already before calibration very close to the sRGB color space, so that no significant difference was seen after profiling.
To criticize is only the very plastic-heavy, cheap processing. If you press here, for example the on / off button, the entire screen wobbles sound is different, but more one can expect for the very reasonable price either.
So the Z24i is highly recommended in sum and terms of image quality, a real bargain.