The main advantage of PVA-based monitors over TN-based ones is in the viewing angles, especially the vertical one. Even the newest TN-based monitors are far from ideal in this respect: the monitor’s colors distort as soon as you lean back in your chair. This is hardly necessary for home or office work but TN won’t do if you need high color accuracy.
S-PVA matrixes take an in-between position in terms of viewing angles. They are better than TN but worse than S-IPS.
Talking about the specific model, the P221W’s viewing angles are wide enough for comfortable work. The image distorts noticeably (fades out in the first place) only when you deflect your head far from the center of the screen. The vertical and horizontal viewing angles are almost identical, so you can use the monitor in landscape and portrait mode with equal comfort.
The classic drawback of PVA technology is that when you are looking at the screen directly (i.e. your sight is perpendicular to the screen), dark halftones merge into black and reappear when you look at the screen a little from a side. This problem is solved in the P221W by means of factory calibration which raises the brightness of darks a little. As a result, every tone of gray, starting from the darkest ones, can be discerned in test images. Darks get brighter when you deflect your head left or right.
Interestingly, the brightness of darks was reduced after calibration with a Spyder 3 Elite and the above-mentioned problem of vanishing darks reappeared but I could solve it again by adjusting the level of black in the monitor’s menu (the Black Level option in the first tab).
Otherwise, I have no complaints about the monitor’s color reproduction as perceived subjectively. The temperature is set up accurately, the image does not look bluish or reddish. Color gradients are reproduced with barely visible banding.
The response time is very good subjectively, with barely noticeable RTC-provoked artifacts (there are light trails behind the letters when you are moving about windows with text).
When the Expansion parameter is set at Aspect, the monitor works correctly with popular resolutions that have an aspect ratio of 4:3 (e.g. 1024x768) or 16:9 (e.g. 1280x720). When you choose some odd resolution, the picture is displayed with distorted proportions or smaller than the size of the screen.