I was debating something similar, Got caught up in the CV vs GT transducer debate. Wound up with a CV transducer, LOVE it. For the Lowrance video you referenced, and as already mentioned, its VERY one sided. When i watched it, their where no responses from lowrance when they where questioned, in the comments section. They deleted the video instead.
Get as big a screen as you can. Do you have a smart phone? Imagine trying to view SI, mapping, and DI on it. You will not see enough to matter, and you'll wind up straining your eyes to the point of needing glasses, or better ones.
Have you thought about used? You can get a bigger screen, more features.
The plus to quickdraw, on units with a microsd card slot, all you need is a store bought card. You do not need a $100 zero lines card. Go to the store of your choice.