Thanks for that, but my main problem is that I don't really know the exact affect that a monitor's response time has on variable degrees of FPS.
I've watched reviews on the Asus PB278Q and they say the ghosting is minimal, but they also don't state what FPS they are achieving.
I would assume that the higher your achievable FPS are, the more likely your monitor would need a lower response time in order to avoid ghosting and streaking.
The Asus PB278Q is listed as 5ms but I'm sure that would be the gtg and not the btb which is obviously more relevant.
Basically I don't want to spend a lot of money on a near top of the line system and $700 on a monitor, to find out that my computer's FPS are out pacing my monitor's response time to the point that it looks terrible.
Your FPS will be completely unrelated to the response time. You aren't in danger of achieving FPS too high on that monitor with anything less than 2x GTX 690. 5ms GTG is just fine for a gaming monitor.
If you aren't playing FPS games, then a monitor's response time is basically a non-issue for you. You just aren't going to be making the constant, high speed turns in other genres of games that will make input lag or ghosting apparent to you.
Now ghosting is one thing, that's when the display panel has slow pixel response times and you can SEE blurring due to groups of pixels changing colors slowly. Most modern displays, whether TFT or IPS, have GTG times low enough that you will probably never see this happen.
However, input lag is probably what you are really thinking of, and that can be an issue depending on an individual's sensitivity to it. Input lag comes from the image processing electronics that drive the display panels. When you have high input lag, you might be able to feel sluggishness in control when moving the mouse quickly. While GTG times can contribute to felt input lag, they are not the sole reason for it. The quality of the image processing electronics are the real culprit, and so, the only way to know for sure what kind of delay to expect with a certain monitor is to read reviews that specifically test for it.