I am looking for personal experience or just opinions about who would be the best company to go with for my upgrade desires. I have been in contact with several companies, including: HPA, EIP, APR, Streetwerke, and 4induktion. I have also read some horror stories from dissatisfied RIP...I mean EIP... customers. So far, I am impressed with HPA's FT400 or FT450 kit, but damn are they expensive. Any repsonses are welcome.