Justin Del Campo

Hey Guys,
Sorry in advance for the length of this. I have a 2011 Audi S4 and I have been wanting to tune it for maximum performance. I did a little research and I came across GIAC Software. There is only 1 place that sells it in all of GA (Eurotech Atlanta is the business name) so I don't have multiple options. I have a few questions for you guys to get a better idea of what exactly it does and if it's worth the money. Below I have copied and pasted the information from the website. Let's

Assume were talking about Stage 2 software, the total cost is $2400, and the car is stock (it does look like the owner before me put an aftermarket intake on it though).

StageDescriptionHorsepowerTorqueXplus This calibration is designed to work with otherwise unmodified cars, however for maximum performance, we recommend installing a(n) intake, exhaust on your vehicle.65 - 110 HP30 - 50 Ft/Lbs
Here are my questions:

1) What is a reasonable price to get stage 2 GIAC software coming from a stock car?

2) How noticeble is the increase in HP and torque?(as in when you first drive it after on a scale of 1-10 where 1 is "Damn that' it?" And 10 is "The extra torque just made me crap myself. This is awesome!")

3) Is GIAC just a company name or is GIAC a type of software that multiple companies sell?

4) What other tuning/software options are out there that are better than GIAC software or that you would recommend over them?

Thank you in advance for your help guys!