You really don't want anything smaller than a 5" screen and if you are planning to use split screen then a 7" is really about the smallest you can comfortably make out the detail. I learned the hard way. I have a HB 365 combo and it is really hard to make out much on such a small screen. I put a 7" Lowrance HDS7 touchscreen on the console and will look at the HB Helix in a 5" or larger for the front once I get past Santa Claus. Yea him, gotta take care of the kids and grandkids.