I must be using my 997 wrong. It takes me at most 2 passes to get close enough using the GPS that I can see the object I'm trying to locate on the 2D SONAR. Of course, I just slow down to about 1 mph and use the display to pass over my target. I don't use the "navigate to" feature.

It is far easier for me to find a previously marked brush pile with my 997 than it is with my LCX-27C. There have been times where I have given up on the 27C and switched to the 997 to find what I'm looking for.

Has anyone tried turning off the SONAR function completely to see if GPS update rate improves. If the processor is saturated with both GPS and SONAR calculations, about the only way to get significant improvement in GPS function through a firmware change is to sacrifice SONAR performance. I'm really not in favor of that.