I'll weigh in here. I run a 3.6 LC KB after running the 2.8 non LC unit. The LC was an improvement and I LOVE!!!!! my car. I ran HPDE about once a month for the last 2 years. I'm running the Revan Racing Radiator and Hx(sold by Shelby) which is the dual fan, double core setup. I think it's the best cooling setup on the market. The fans are set to come on with the ignition(not on temp) and my thermostat is set to open at a lower temp. With all that, I still get heat soak in warm temps(above 80 degrees ambient). If I short shift I can hold it off, but if I go hard, in 2 laps I start losing power. I run VIR & Summit Point most of the time. VIR is worse because of the long straights and more WO time, but it happens at both tracks. The better you get at driving, the longer you will be at full throttle, the faster the heat soak comes on. When it's cool outside, it's alot of fun. But most of the driving season is in the summer and that makes it tough. If I had it to do all over again, I would not go with a FI car. I'd build a monster NA motor and have fun with that. The heat issues are a killer. NA in the long run is cheaper. Also, one thing you probably arent considering is fuel octane and mpg. Once you start making big hp and heat, you will need to run 98 or higher octane fuel to fight off predetonation and grenading your motor. I know 2 people who have done this with FI motors and both teardowns showed heat due to predetonation. So I just run the 102 octane just as insurance. I have never had a problem, but the stuff is $7.5-$8/gallon. That SC forces air and FUEL into the cylinders. In a 25 minute session, I will use 10-12 gallons of fuel. That's $75 plus per session in fuel. Yes my tune is a tad rich, but rich is cooler and also helps with predetonation. There is alot to running FI motors and making them last. Cooling is critical, as well as your knock sensing setup. I had experienced, knowledgable people do my setup and as I said I havent had any problems. But I know quite a few people who have had problems. You cant just bolt on a bunch of hp w/o taking care of the total package.
Think long and hard about it. 20-30 minutes is alot longer than a 10 second 1/4 mile run. People are experimenting with meth injection. I dont have any data on that. But, it's just another complication and more weight on the front end(which is something we didnt even discuss).
Goodluck with your decision.