I was reading reviews on bps about the TI2. One guy said the downscan frequency could not be changed. My question is how big of a deal is it to not be able to change it? I have 1300 hundred to buy a fishfinder and I’d like to buy the 9” ti2 but if you guys think I’d be happier with 7” HDS live I’ll buy that. Keep in mind I’m just learning how to offshore fish.