M3 exhaust tips are the same size, not staggered. 997.1 PSE cars, on the other hand, look like this:
...which happens to look ridiculous. Please don't do this!
Also, the 458 barely manages to get away with the triple exhaust thing because it's so awesome otherwise. On a 350, that is going to be chav central and then some, I don't need a 'shop to know that.