I did not install tab indicators on my 3560, because I am a DIY'r and the Bennett system is a more complicated install plus requiring haul-out.
On my prior boat with Lenco tabs, I did add the indicator switch and loved it. That said...if you want to have it installed, I think you will like it.
Two things I have added to the my present Bennett system, are the auto-tab retractor and the auto-tab controller. Both are easy to do yourself.
The ATC is way cool --as it controls the tab setting automatically once you set it up for the way you like the boat to run.