Have a new 959 HD DI unit coming in this week. Going to exchange the standard traducer for a trolling motor transducer. Looks like I have two choices. The XTM 9 DI 25 T or the XTM 9 Wide 20 T. The differences seem to be in the frequencies and the beam width. I fish mostly shallow water, less the 50'. What would the differences be using different frequencies on DI and what gives the clear view?

XTM 9 DI 25 T Down Imaging/Dual Beam Plus, 75'/45', 455/800 kHz (DI) and 25'/16', 200/455kHz. Specs match standard transom transducer.

XTM 9 Wide 20 T Down Imaging/Dual Beam Plus, 75'/45', 455/800 kHz (DI) and 20'/60', 200/83kHz

Any input would be appreciated.