I installed the Nautic Laugic NL4-PP (PerfectPass) into my 2004 Gravity XLV. Here is the install guide for anyone interested http://ddixonphotography.com/nl4-pp%20install.pdf.

I was looking to upgrade the PerfectPass that came with my Gravity XLV to Star Gazer. Since I had a single line display the upgrade cost was a lot. Then I found the Nautic Laugic option which saved me enough money compared to the Star Gazer for a new prop.

I must say I'm very happy with the product. No more calibrating the PerfectPass and dealing with the issues of a paddle wheel. It keeps a great consistent speed and smooth operation. I also hooked my speedometer into the NL4 so I have a GPS speedometer now as well.

Nautic Laugic is great to work with, very responsive to my emails. If your looking to get GPS accuracy with out a big hit to the pocketbook take a look at Nautic Laugic.