Just wanted to add my 2 cents worth.

I received my Sprint Booster today from SLKfans.com.
Communication was excellent. I am in Australia so it took a couple of confirmation emails 'cause my Paypal listed a PO box and they need a street address to deliver. Then I wasn't home when it was delivered so redelivery meant that I got it today. All in all, 17 days from order which I thought was pretty good.

As for the performance itself, my first impression was that it was quite disappointing.

I do like the change of shift pattern- tends to kick down a bit easier.
Acceleration difference isn't all you guys churched it up to be.
I definitely didn't get that "WOW" feeling.
Obviously I'm going to have to drive it some more but I will definitely have to look at getting lower gearing in the diff to help it along a little.

Before anyone says "what do you expect for $300", I know it shouldn't transform the car into a V8 but I'm definitely not going to have to relearn how to drive the car. In my old Chryslers, I would have a similar result by removing the kick down rod from the car, give the knuckle a couple of turns and put it back again.

Yes, I know technology has changed but it seems that the Sprint Booster would work best with other components 'cause on it's own, the difference isn't enough to write home to Mum about. Just my opinion.