I built my own RV8. I have over 5 years and 2800 hours of build time. After flying my RV8 for about 45 hours, I tried the Eye Aligner. After determining I was sitting about 2 inches too low, I made adjustments in the cushions and seat. My visibility and landing improved dramatically. I wish I knew of the Eye Aligner during the build of the interior. It would have saved me time and money. The landings are so much more comfortable now.