Originally Posted by PAULW
I believe you can trust HDDP as far as mod's to XF's, he is probably the best on the forum but I sent my ECU to SI and am very happy with the results and they were very helpful and responsive when I used them, as far as them no longer in business I can't say.
Yeah I thought they were great to deal with and likewise I'm quite happy with the results.
BTW, how do you like the Sprint Booster in addition to the SI chip? Did you get it first or after the SI tuning?