The Asus VG248QE is THE best gaming monitor for the price due to its affordability, features, and build quality.
This monitor is, in my opinion, the perfect size to meet the needs of someone who plays multiple genres of games. I play a MOBA, an MMORPG, and various other titles of different genres off and on and the monitor is the perfect size for all of the gaming that I do. The screen itself is incredibly sharp and offers great viewing from most angles. As is the case with TN panels, you really need to be sitting in front of the monitor for the best experience. If your situation differs, you need to consider paying up for an IPS panel - the cost is significantly higher but viewing angle problems will no longer be present. As a side note... to confirm my theory that this monitor is the perfect gaming monitor at the right size, I have seen it all over professional gaming events on Twitch.
The 144hz difference, in my opinion, was incredible and well worth the cost over a traditional PC monitor. You will notice from the moment you set the refresh rate in Windows that your mouse moves more smoothly like butter and you gain so many more frames of vision that you were losing before! One thing that is not explained well out of the box is that you must use the included dual-link DVI cable to achieve the maximum refresh rate of 144hz and a setting in Windows needs to be set as it will default to 30hz or 60hz. I can't recommend this monitor enough to all PC gamers requiring quick reaction times (any game online).
Note: I performed independent research and asked gamer friends for their advice before purchasing and was not provided a review copy. I have no involvement with Asus though I am very impressed with them now.