Well as far as lag, rear mount you will always have lag, is it a boggy lag???, Well at 9 pounds I have as much lag as a stock nytro so I guess I don't really feel any. I'm a drag racer so response is critical to me. At the higher boosts, hang on to your shorts. It's not a front mount but closest thing to it.I've driven the mc express kit on the nytro at 18 pounds and I have to say it had lag, not alot , but all hell broke loose after that, (just my thoughts)