I was referring primarily to fish on SI ..... At the higher frequency the fish image will likely be smaller due to the increased resolution .... kinda like the difference between what fish look like on DI compared to what the look like on 2D.....That's not a bad thing.
Decreasing range or zooming should result in a much better fish image.
The dedicated DI element in the transducer is another thing all together .... it should definitely give much better DI images.