The Rosso twins are
Join Date: Oct 2011
Location: United Kingdom
County: Tyne and Wear
Never fitted one to my Alfa, but I run 2 VW transporter vans for work and fitted something like one of these to one of them to see if it could improve fuel economy a bit (as it stated it could) as they cover around 100k a year between them.
It wasn't as cheap as this, around £70 and was just a plug and play job, and to be fair it did make the engine more responsive and for a bit it was getting a bit more mpg as long as you didnt use the extra power.
But then after about 2 weeks or 1000 to 1500 miles it started feeling a bit grogy so i whipped off the box and took it back to the company I got the van from (playing innocent of course).
I think the repair bill came to around 2 grand with new injectors, filters and a few other bits thrown in(plus labour of course).
Didn't cost me a penny thankfully but I wouldn't touch one of those again if they gave them away with a free weekend with Sara Harding, but it's your choice.