...3) I actually had originally tried to upgrade to the brembo 4 piston kit from american muscle when I first installed my procharger but UPS kept damaging the calipers because of the poor packaging from ford racing. If I decide to buy this kit again I would probably go with the vorshlag kit or someone who ships Fedex because in my experience UPS is terrible when it comes to damaging packages...
We use FedEx, UPS and USPS depending on who makes the most sense, but, the important thing is that we don't drop ship these sorts of parts. We have them at our shop (usually in stock) and repackage and wrap them so they can be shipped safely. It sucks to open a package and find damaged or dinged up parts.
But your main question, should you upgrade, yes. You should. The change in modulation and brake feel alone is worth it. Longer life span of the rotors and pads is another. And should you decide to dip your toe into some more aggressive sports, you'll be prepared.