Will be buying new electronics next spring and will probably be Humminbrid helix 5,7,8, or 9 inch. Would you get mega si/di on console and bow or maybe just the di on the bow which is the way I’m leaning thanks for any and all input 

I’ve had both at both places for years.  I rarely use si but I use di all the time.

I want the best at the helm for navigating with all possible info and don't need the top of the line at the trolling motor.  Although if bucks didn't matter, I'd have the best both places.  Now and then I wish for more up front.