To the OP:
Well in the end you have piece of mind, you know that the tune has all the supporting mods to safely support the engine tune. I would even go out on a limb and say that Dinan has a TON of room to add more power with the required oil cooler and intercooler for the stage III car.
If this is a car you keep indefinitely, you have all the supporting mods to increase your chances of having a trouble free/durable car (all relative of course).
But as most enthusiasts that hang out on the forums, we get numbed pretty quickly after initial mods, and are always craving more, and when we get to the point where there is not much more modding that can be done, a new project must be started and the old project is usually parted out and sold.
Wow....our hobby is a true money pit...BUT Damn it's fun.