I think of the TFT like a TV screen, you can change channels or project whatever you want (within reason) where as the old school dash board is set from the factory to what it can do, (although I may be wrong).
My TFT shows all the levels I added, I only put in 4 as I figured fine tuning any more was unnecessary, will see how it feels.
If you use 4 then you only get one none indicated level, the highest? Maybe less confusion.