I can only speak on Lap3, never had experience with jb4 or KSR. I have my dyno sheet posted in my gallery so you can see the power band is pretty smooth (forgot to tell them redline is 7200), the car is running Garrett 3076/WMI/Lap 3 ecu running stage 4.5 tune. As far as anything with the actual tune, for not being a standalone ecu its about as clean as you're going to get in my opinion when running WMI. your local tuner will have to make some fine tune adjustments after you install the ecu. Now i did have a short period of time when the WMI modulator was broken and had to run the Stage 4 tune. I will say that tune felt a bit..rough. There was a big power dip right around 2500-2800 rpm in wot, it would feel a bit boggy followed by a big power jump. It would also run a little rich, it does not run rich with WMI. Also Keep in mind that once these cars start making about 300whp they like to jump left, especially in lower gears if you drive in paddle shift. I would suggest in stickier tires and stiffing up the chassis.