staggered offsets on FWD

[Entity]

I've read some people say that staggered offsets on FWD cars are highly illegal... why is this so?

also, if staggered offsets is illegal, how about staggered widths?

can i run 7.5" wide rims at the front and 8.0" wide rims at the back on my euro legally if they are both the same offset?

reason being, i really want this set of wheels but the offsets on the front and back are +2 in difference.

[bennjamin]

staged widths are illegal too - on a FWD (ive been told)the front and rear tyres need to be the exact same size and dimensions...ofcourse a spare tyre is allowed on.