The problem with exhausts is that you are getting no power gains and noise is subjective. Picking an exhaust from a video clip is daft IMHO as cameras and mikes vary. Going to meet is a better idea but standing around outside the cars is only half the story because that's not what you'll hear. The only way to be sure that you like the sound of an exhaust is to get inside someone's car and hear it throughout the rev range and on the motorway at your usual cruising speed.
Now most of us don't have that luxury so we come on sites like this and take recommendations before taking the plunge. On that basis, the NISMO is undoubtedly the safest choice as there are tons of owners with it and a clear consensus that its a fine sounding exhaust, not to loud, not too chavvy and pretty good quality (it has been known to split...). IMHO anything else you buy you take more of a risk with as the user sample is far smaller.
HTH