Pro charger question

Yikes!!!! These things are expensive! Performance gains are really big though. When i was on hold at ati procharger they had a 12 second nova that they put a procharger on and it ran a 8.62 @ 166mph on 91 octane pump gas. Thats nuts. If I had the funds ($4600) I would definatly put on on my dart. Thanks for all the info.