The response times quoted by manufacturers are not that interesting. There is a whole lot of other things that determine the fitness of those LCD's to play games, or even the actual response times.
For starters, what do those numbers mean? What does it mean, having a response time of 8ms? Full screen or single pixel? From dark to bright and back, or the other way around? What technology is the display using? And what about the delay? Which delay? There are multiple.
Normally, the time it takes for a single pixel to switch from off (dark, normally) to on (bright) is less than the time it takes to switch the other way around. Capacity and all that. And each technology has it's own relation between switching single pixels or an area, and the amount of "bleeding" that happens between adjacent pixels and slows the transition. Or even the time it takes to update a full screen, or only the pixels that changed.
Whatever. In short, all this means is that the time specified is the best case of a single pixel switching the way it does best and disregarding everything else. If you want to see if it runs games well, go take a look and see for yourself.