To me it seems rather overpriced but an interesting idea.

It's supposed to remove the DBW throttle delay and make it more like a cable throttle.

Basically by changing the characteristics of the pedal.

http://www.sprintbooster.co.nz/

I like this explanation from here

Pedal Travel: |----------------------|----------------------|

Percent:.........0.........................50%.... ..................100%

Spring Booster Travel/Throttle Relationship:

Pedal Travel: |--------------|---------------|---------------|

Percent:.........0...............50%.............1 00%............100%

So you see, all it does is decrease the travel in the pedal in relationship to throttle position.

So where you saw 1/2 throttle before in the pedal, will now be (for arguments sake) 3/4 throttle.

Essentially making response greater, but adding no power whatsoever. I actually was considering it because the drive by wire lag gets annoying and even makes my lightweight flywheel seem sluggish responding.

Some interesting opinions here:

http://www.vwgolf.net.au/showthread.php?4395-Sprint-Booster-Installed-and-lovin-it!

Everyone who has one says it's great.

Sounds similar to the Pedal Box - http://www.diesel-performance.co.uk/box-details.php?id=15 - that a few members here have used. Price is similar too.

At that sort of price id get a remap and then you deff will have more throttle response

Total utter snake oil

You can program a FBW throttle to behave however you want it, and they're not slower responding than a cable - their faster !

Exactly, it reprograms the throttle.

But how would you program it? Part of the map?

Yes, part of the map

You can program it however you want

If you wanted 75% of the throttle controlled by say the last or the first 25% of movement of the pedal, this is programable

Most mappers put a more aggressive throttle response into their maps to aid the impression of more immediate power

The downside of an aggressive/sensitive throttle map is reduced MPG (unless you've got cruise control)

If you wanted fuel economy a throttle map like this would be better

Pedal Travel: |----------------------|-----------|-----------|

Percent:.......0...........................30%.......50%.......100%

Super lazy setup

I bet they would sell well at 1/5 the price.

My track car was remapped to have linear throttle.

It is like driving a normal cable throttle car now (so you can actually balance the car with the throttle pedal through the corners).