Is adding sythentic oil to my 99 cadillac deville better in any way?

I have a 99 Cadillac De Ville its running smooth i was just wondering if putting synthetic oil will boost up the engine so it can run smoother.It has 110,661 miles and I live in a city thats always 100 degrees or higher.Ive also heard it saves gas,is this true.??|||Synthetic Oil is usually more benefitial to newer cars that you start them out with. Since your car is used to the regular crude, it really wouldnt have any noticeable difference in performance.|||Synthetic oil is far superior to mineral oil, it has better lubricating and flow characteristics at high and low temperatures, doesn't break down as fast as mineral counterpart. It also resists moisture far better. It doesn't matter if your motor is old or new, synthetic oil will pay itself and you will notice the overall difference.