The unit on the Lowrance website does not come wtih a transducer. The one at Cabela's comes with the Total Scan transducer.
If you are trying to get all the bells and whistles, buy it from cabela's.
I have no clue about the Helix. I have only used Lowrance for the past 15 years. So, I am going to recommend the Lowrance. But, that is my personal preference, Ford, Chevy, toyota, Dodge and Yugo.
Hope that helps. I'm sure a Humminbird, Garmin and Raymarine user will chime in.
Best of luck. I'm sticking with what I know.