if i recall this question has been asked before parus and i dont think they are a straight swap .

im running a nc29 race system on my nc23...it all bolts up...kinda.
you need to shift the chassis mount(or cut it off) and make up a new section to the muffler
easy mod
as for this brand of zorst...my issue with this brand that the collecter in the pic just looked crap,and would proberly be more of a hindrance than a performance gain
you get what you pay for...and sometimes even get ripped off
stimpy

doesnt look too different to the "kit" system kawasaki used on their F3 zxr's .. and they work ..

as for quality, ive got a delkevic system on a zxr, and I cant fault it.

still looks dodgy
hrc(even the copies)
beet in stainless or Ti
graeme france's race pipes
all have a more flowing collecters than the 1 in that pic...
to me,it looks like they have just expanded a bit of tube and welded it on
no offence to the owners of this brand
just dont like what i see in that pic
stimpy

i tend to agree with stimpy above (tube expansion) ive got the 4 2 1 and nowhere near that bad on craftsmanship (still not the best ive seen), only clicked on the link at start of post for first time and parus if you look at buying these i paid less than that with postage from mad4bikes (albeit/although your from overseas.)