Here are three clips that I have. The first is the gt34uhd which is the gt54uhd without 2d.
The second one is the Gt36uhd which is the gt56uhd without 2d showing a rocky bottom.
The third one is also the Gt36uhd showing a grassy bottom.
If you’re going to be fishing in 25’ or less I would save your money and go with the gt54uhd.
If you’re going to be fishing deeper than 25’ I’d go with the gt56uhd. I personally don’t think
the image is much better with the Gt36uhd than the Gt34uhd but it’s got so much better
range and I fish deeper than 25’ most days and it was a big improvement over the gt34uhd.