I had one on my S3. A brilliant bit of kit, and ideal for putting back to standard at service time, just to keep the warranty. It also has an immobiliser feature, where you can effectively remove all the mapping from the ECU, so even if someone manages to get past the factory immobiliser, they can't get any further.
It's simple to use, and takes about 15-20 mins to swap maps either way.
Obviously it's only a generic map, unless you get Superchips to do it themselves at their HQ, so I did swap to another map later after I'd added other stuff, but if you're only wanting a remap, and don't plan to do many other mods, it's great.