Anyone with experience of powerchips for ahu

As title, I am contemplating one of these for my ibiza. Does anyone have any experience of these?

http://www.ebay.co.uk/itm/SEAT-IBIZ...arts_Vehicles_CarParts_SM&hash=item4aa545a757

 

not personally, but for the money, its got to be worth a punt?

 

I've just bought one of these for my mk2 abf off this guy. Seems to make the car go a bit better I put in an offer 10 cheaper than his asking price so maybe worth trying that again. Took a while to arrive tho