I think that most people who found that they needed a glidewrapper followed the lead of others who were already using Zeckensack's.
Ralf found that running in glide gave better frame rates on his rig. Others used it because it gave horizon fog.
This thread started because of Stratos' recent thread. He was not getting horizon fog in d3d, and I have the same problem. I advised him to use a glidewrapper, and was looking for a link to Zeckensack's when I came across a review of several, including nGlide. As nGlide seemed to be much more recent, and even windows 7 compatible, I thought that i would check it out.
For me it has several advantages, especially the screen size availability, and I recommend it.