#1. Shipping is FAST...I ordered on Thursday with normal shipping and found the box on my doorstep when I got home Saturday.
#2. Installation is straightforward but a bit of PITA due to dealing with a variety of clips and fasteners that can be difficult to put back together (i.e. the Aircon filter and cowl was a pain to re-fit, as was the lid on the ECU with the additional wire running into the box). I took a total time of about 2.5 hours double checking each step, although I'm sure that if I did this again it would be half that time. Once it was hooked up I got no CELs so taking my time paid off.
#3. (Most importantly) Performance is immediately noticeable...I've tuned prior cars (C5/GTO/SRT 8/Mustang) with handheld tuners/CA intakes and exhausts and the JB Stage 1 on its own (I have not changed anything else) is much more noticeable than any of the others for a fraction of their price. While there may be no replacement for displacement, mild turbos offer a great platform for juicing HP.
Overall: Very happy with the JB...huge bang for the buck.
Some others mentioned they felt the mod kick-in after the car was driven a couple of times. I finished the wiring last night and started the car for a few minutes in neutral as night fell (couldn't tell if the tuner had done anything but did confirm the installation was correct). This morning I re-assembled the bits I'd removed, drove the car and the change was immediately evident.
One tip: I thought the small control box might rattle around the ECU compartment so I velcroed it in...