The verdict is the same as for FP91V+ - the monitor lacks preciseness and belongs in the C classification.
At least the brightness is at a good level, which means that this monitor is more than acceptable for occasional office use, especially since text was fairly sharp. But for photo retouching, the monitor is unfortunately too dull, and it lacks a little fidelity.
Gaming, on the other hand, is an area where the FP91VB excels. It's a hair faster than the FP91V+, but you'd have to have a very good eye to be able to actually see any difference. But the quality of the interpolation is better on this model, which will make gamers on a budget very happy.
The video performance left us with a somewhat unpleasant impression. Video noise was omnipresent, especially on shaded colors and in smoke effects. That's partly the result of poorly controlled overdrive. What's more, the vertical viewing angle was too narrow. If you're not directly in front of the screen, the colors turn reddish. Finally, flesh tones were a little yellowish, which means you'll have to make a lot of adjustments to get them right.
The FP91V is neither better nor worse than the FP91V+, which may be why BenQ has kept both models in its catalogue. If you like optical filters, you can spring for the FP01V+; otherwise the FP91V will do. But clearly there are better choices than these two monitors in this category.