For info for others looking thru this thread, Pedal Commander and Sprint Booster are not just the same thing rebadged - they're different products made by different companies but they do more or less the same thing. It sounds like the Pedal Commander may have a more sophisticated control setup with various modes and then levels within those modes. Sprint Booster just has a number scale from 1 to 10 - displayed on the little controller. We run our SB at 5.
The straight up feel of the SB - and it sounds silmilar for Pedal Commander is that instead of pressing the pedal and waiting for things to happen, the response changes to feel like the accelerator is actually directly connected to the engine - ie. the vehicle directly responds to the pedal - you press the pedal, the car GOES - simple. I really dont think I could tolerate driving our TH without it now.
Yes it's a few hundred bucks that could go toward a "proper" tune - but in reality ur looking at close to $700 for a tune and no one yet has stepped up privately to offer the assistance of supplying owners with a plug and play OBD module ready to go with an optimised tune for std car (if/when I finally bite the bullet and do a proper tune as described in Tylers guides I WILL then offer that help to fellow KL owners) - and neither have any commercial businesses - so to get a tune done there's the money PLUS all sorts of messing about to get it working. Enthusiasts might say its all easy - but for someone who just wants their KL to go well it's really not. A pedal module takes about 10 minutes to plug in and instantly TRANSFORMS the car...
I know on paper it's supposed to be as simple as remapping the pedal so full throttle is reached much quicker than full pedal, but it drives as tho there's more than that going on - else that simple remapping has results that aren't readily apparent in theory. For example on the face of it you'd expect the trans would respond as tho the normal pedal was being held down further - ie. holding gear and changing late etc. but in fact no, the shifts seem to come thru quicker and slicker and kickdown doesn't happen as much as when just running normal pedal map. When my wife used to drive off down the street I'd hear the engine revs running quite high like it was holding second for quite some distance as she accelerated away - actually watching, there seemed like a lot of fuss for not much action - but with the Sprint Booster, the car takes off quickly with lower revving and quick, slick gear shifts. You feel that when driving as well of course.
I actually wonder whether there's two signals from the pedal - one for engine and the other for the trans - and the SB only conditions the engine signal. That would explain how the car drives - ie the trans is seeing lower pedal input and matching that to actual revs with predictable - and NICE - results. Even if that's not the case (and I suspect I'll be told so fairly quickly) it's certainly how it FEELS.
7:22 in the video I've posted above sums it nicely...
I enjoy shocking people as I walk them off the line on the street... I could never drive the Cherokee without the PC on. 
