This is my first post and i just wanted to say what's up to all you volvo lovers. I have recently purchased a 2005 s40 t5 with manual trans. It is expected to arrive in the dealership in about 2 weeks and I am very excited about the purchase. I am considering buying an after-market performance chip to increase hp and torque for the car. I was wanted to know your opinions are on making this move. My buddy who know everything about cars is against me getting it bc he thinks it will void my warranty by probably harming my engine. He also doubts the gains claimed b/c it seems to him like just the "usual generic universal ebay radio shack crap" part. Here is the performance chip I was considering:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7962369215&category=33598

What are your thoughts on purchasing and installing this on the new s40 when it arrives?

If I were you I would contact them and try to get tons more info.It says money back garranty but that doesn't mean that it will even fit your car.These new cars with all the computers are weird.I would make sure they tested it on an 05 S40 first and see if they will give you a copy of the results.
It does look pretty cheezy but it may work who knows.