Humminbird HELIX 15 CHIRP MEGA MSI +

Only used it once for a test run. I would much prefer the 12 inch model. The 15 in size ie great but they are not the same units. The 15 has horrible color choices esp on the maps. The DI and SI screen is NOT clear like the 12 in version. There are other differences in the software too. Not sure that more choices is better.