The simplest, most direct route to setting up display, a PC monitor will provide decent quality and is usually the cheapest. Also it is the easiest to set up. As opposed to a television or authentic arcade monitor, all that is required is to plug it in.
However, as stated before this price comes at a cost. Games tend to look "pixelly" (blocky looking graphics) due to the high resolutions that PC monitors run at. Enabling scan-lines (black lines across the screen) can make the quality better but it still does not compare to the quality that can be achieved on a television or better yet, an arcade monitor.