Full screen, color 30.
In my early days I used to find it very distracting having those lines flying around the screen. When I got into drawing building systems for large commercial buildings, I saw almost everyone using full screen. It finally dawned on me that it made navigating around the plans much easier and like you, Bob, I use it for a quick alignment check. I set my grips small so I can easily check insertion and midpoint alignments, also.