I have personally used it on a fair range of vehicles with a variety of issues

To be fair I'll be up front and disclose I have been involved from the start introducing the fluid to the automotive specific market. (It was developed originally for cleaning turbines in jet engines and power station turbine generators, as well as adopting for large marine turbo diesel engines, so has plenty of history in high-value markets that need it to work.)
But seriously, I'll avoid trying to sell it and give my personal experience of how it works - I have done for example a number of VAG group models (A6, Golf, Beetle, Octavia), Ford Mondeos of various versions, Mercedes A-class, Vauxhall Astras to name the ones that come to mind, all diesel turbos. The cars had a variety of issues from vague driveablity problems, with hesitations and slugish performance, through to hard faults due to sticking turbo vanes causing overboost and limp mode as soon as any load is applied. In every case the owners have reported at minimum, significant improvement and in most cases a transformation of driveability and power back to how it should be, and often reduction of exhaust smoke and potential fuel economy improvements.
Application is straightforward and involves introducing the fluid into the air intake (after the MAF sensor) as a fine spray in three stages at various rpms as described in the instructions supplied with the bottle. Whilst not actively marketed to individual public end users, it is available to garages and "enthusiasts".
To briefly explain how the material works - it is a water-based non-toxic material with a "surfactant" active ingredient. This works by the molecules attaching themselves to oily/carbon deposits in the air path (ie turbo compressor, intercooler, valves, possible EGR and exhaust turbine components) and then releasing them as tiny particles into the airstream, thereby stripping the deposits in thin layers deliberatley avoiding large chunks of material being dislodged and causing subsequent damage or blockage. (remember the jet turbines? they can't afford to have damaging particles passing through) There is no solvent as such in the material, and is not intended to "soak clean"
A significant number of units have been distributed since launch and feedback has been enthusiastic to say the least. It is important of course to diagnose the
problem correctly in the first instance to be due to carbon/oil fouling for the treatment to be effective. Mechanical or electronic issues (including severe clogging which is verging on mechanical siezure) producing similar symptoms will of course not be magically fixed!

It is also equally important to consider the possible reasons for the condition and establish if any other remedial work is required to avoid the condition recurring within a short interval.
Hope that helps
Edit - relevant post from Bill (ibizacupra) on this one too -
http://www.seatcupra.net/forums/showthread.php?t=346219