I currently have a Garmin 188 and have been please with the performance and quality but I am now looking to upgrade to a unit with more capabilities and a larger color screen. The boat is a 22ft aluminum boat with hard top. Fishing is mainly large river/lakes and ocean fishing out to 30 miles. <br /><br />As a result, I have narrowed down the field to a Garmin 3006C w/GSD20 sounder and radar and the Raymarine C70 with sounder and radar(smallest radome with both brands). I would appreciate any feedback on these 2 units and more specifically: <br /><br />1. Ease of use <br />2. Radar performance/quality <br />3. Navionics Gold vs. Blue Chart <br />4. Sonar performance (is the GSD20 any better than what I have in my 188 and is the HD sonar technology from Raymarine a lot better?) <br /><br /><br />Also, as a wildcard and foregoing the radar option, what about the new 900 series units from Hummingbird? How do their sonars stack up against Garmin and Ray? I know QC has been spotty in the past and they have targeted more inland fishing styles but these new units are interesting.......