That's kinda what I was thinking/going with as well. A full-on meth kit will all the goodies is like what, 6-700 bucks? It's not exactly a ton of money, especially when you pair it with a $50,000 car.
I didn't buy the full extended warranty, but I did buy Tire and Wheel. I live in pothole central. I have no idea how well it works.
I'm not sure if you got ripped off too bad, it's only a couple grand. But I'd probably cancel and get the cash back.
I highly doubt that exhaust, without a tune or a downpipe will make any difference at all. The stock exhaust is highly free-flowing. It's likely you're feeling a placebo, the sound + knowing you dropped a bunch of cash will do that.
From what I understand from reading on the N54 forums.
JB4 + Fuel-It system is the way to go to monitor E content. The Fuel-It system integrates directly with the JB4. That's the route I plan on going as well. Simple.
You need the resonator delete and to remove some of the stock heat shield on the intake to install the AOS. This turbo heat shield is recommended for both.
I did exactly this. + Also disabled the seatbelt warnings (I wear my seatbelt, I just hate it yelling at me, I'm an adult), and did the auto-seat heater thing that @CarGuy11 has, and Sport mode on start up/default.