I dont know which to go for first. I have read through tons of posts, but most just conflict with each other. I can get the exhaust for 698.00, or the boost controller for about 399-450. Some sites say to put on exhaust first, some say boost controller. Some also say a new ATR exhaust will increase horsepower 8-10, and some say it increases horsepower up to 23. Which is more acurate? Some sites say an AVC-R will increase hp up to 30 or 50, but then some say it only increases up to 18. WHY CANT THEY MAKE UP THERE MINDS? Has anyone done either one of these and know what it will produce on a 93' VR4? Which would be better on a Vr4 with only K&N air intake? Thanks!