This year I purchased the Garmin gpsmap 78s with garmin lakeVU hd. I bought it so that way I could have the depth chart while ice fishing and not have to drill holes to check. I have not had it out on the ice yet. However, I did take it out on the open water and compared it to the fish finder readings. I am satisfied with the performance, it is not 100% accurate everywhere, but close enough.