"No map update" option - enable or disable and why?

[jaxa]

I have question about "no map update" option using GWX3.
I like realism options and always wanted to play as real as possible. I play with this option disabled and I can see ships icons on attack map when surfaced or watching via periscope and can't see when submerged - it's logical to me, except torpedo icon running to attacked ship after launch (I'd like to disable it - is it possible?).
With "no map update" option enabled there are no ship icons on attack map - it's rather unlogical for me, because navigator always should sign enemy ship position on map in my opinion. Am I right or not?
Last days I found Assisted plotting mod, mix of full informations about targets and no informations about them. I test it now, but have problem what to think about it - what is closer to real? Enabling "no map update', disabling it or using Assisted plotting mod?
What about your opinions?