Don't feel too bad. I remember when my GT popped it's dyno cherry by putting down a whopping 211rwhp/250rwtq! :shock: That was followed by a mind blowing 205rwhp/238rwtq on a warm pull. :nonono:
That's bs. Many, if not most ppl get theirs dyno tuned, and I haven't heard any such voided warranties. A good dyno tune does make a difference because the KB tune isn't always dead on.
IMO the S197 stangs killed it. 2V Mustang GTs aren't the only ones hurting. Terminators have crippled the demand for 99-04 2V Roush and Saleens.
I'll never sell my GT. I'll just keep modding it and enjoy until it rusts beyond repair.
Get the IC kit because you'll regret passing it up. Over 90% of those who got the non-IC kit ended up upgrading anyways. You might as well do it right the first time.