Well, all I can say is that my curve is SO much smoother now & I get to the power range SO much faster that I did before. Granted, I also had the air/fuel mixture adjusted after I did the intake. I am very pleased with how it rides. It is very smooth & sounds extreemly tough.
I did ride it with just the intake mod for two days but I didn't get on it to much until I got the leanness takes care of. I didn't do a dyno before & after each mod so I can't say for sure that it was better or worse with just the intake mod. But, by the seat of the pants it felt better during the riding that I did. It could have been completely psychological however.
It's necessary to also do some type of air/fuel mixture adjustment to ensure you are not running lean. Burning up the engine would definately be a bad thing.