Modifications to my Ferrari?

The 'Pro' would be having your car modified to your specifications with precisely the additions and features that you want, ultimately making you happy.

The 'Cons' would be having some hack tearing into your electrical system, voiding any warranties you may have, potentially causing expensive and hard to diagnose issues down the road.

Since you are talking about a dashboard display, you are probably not talking about a car with collector value, so the usual arguments about keeping it original are really a moot point provided the procedure provides you with the satisfaction ginen by the aforementioned 'Pro.'

That said, I think it all depends on who is doing the work. Electrical work in particular can be very, very challenging if not done right - I will admit my MG and Triumph history may bias me there. With today's more sophisticated systems, I think it's all down to the knowledge and skill of the person doing the work. If they do it well, great. You will love it. If not, you will curse the day you decided to try this.