What water do you fish? I have an Elite-7-HDI by lowrance and it has been awesome. The HDI is only really useful on pretty calm water though, you will see little ripple waves on your screen even so there is a learning curve even on relatively calm water. The plus side is the imaging, I have seen crabs, old boats etc and incredibly good imaging of weed/kelp beds on the bottom. For salt water fishing I only use the HDI for really calm days when bottomfishing, I use it a lot in lakes or rivers though. The standard sonar on the unit is great as well, it took me a little bit to get it tuned just right though. My own experience with lowrance service has been good but I only called to replace a damaged transducer.