Does anybody know if this will be alright?
Its from the states and i was wondering if there are any differences

I got my exhaust done on saturday by the way, the bstrd cat is on the manifold so i couldnt have a de-cat the guy that owns the place said a angled back box wouldnt fit right and would look gash so i went for a 4.5 straight cut back box, looks alright, doesnt look stupidly big or anything, makes a nice noise but its not really loud at all

Although just coming back from work now i gave it the beans and it made a mahoosive amount of noise with no other cars on the road, proper all around you kinda noise, but driving normal it barely noticeable so i HAVE to have a manifold and de cat or i wont be happy.

or i might get the xs power actually, which is best?

Yup, thats correct. It will just take a reading from one cylinder/pipe - in practice this will make no differance at all to exhaust emissions or fuel mixtures... Mine even ran fine with the Lambda disconnected and the hole blanked off, as I had difficulty removing the sensor from the old manifold at first.

i personally dont think its the headers that give you extra volume - its the changing of the cat that does. A sports cat does make it louder, and decat even more (but in a horrid way)

yeah - you know where the second bung is by the flexi pipe - the wiring was extended down to there - i know what you mean though ive never heard if it before either - but it got the readings down...