Check my sig, I installed mine last march, on my 98 Jetta TDI with 218,000 miles on her and she loves the stuff. I'm going to be replacing my injectors so I can pull them in 10k, 20k, 30k miles to see what they do to them.
So far I drive about 35 miles to work each way and its running great. I haven't had any problems with the set up, or installing it.
Let me know if you have any specific questions you want answered.