Jim,
Mesh doesn't come in colors. Unless you're staring at a GeoTiff file. Are you thinking orthoimagery??
Checking some compression numbers on some files. Using 97% vs. 100% resulted in a 60% file size drop. Going to 95% is over 70% file size drop. Mesh, I'm talking about.
Orthoimagery may be different, but there will be a big difference with just a little compression.