Here is a sample of a fake N98 track top that can be picked up for 1/6 the price from an official one and some of the attributes you get with a fake.
From a distance its fine and looks good.
Badge is well created.
Quite good swoosh.
Pockets are OK. But you will notice the zip has a lesser quality about it and the zip lining is noticeably less feel about it.
The sleeves are good replicated
An obvious defect is the main zipper. It the wrong way round. Its got no logo and its nowhere as smooth as the real ones. Not YKK or SBS, CMZ quality to say the least.
The collar is also less shaped. The Nike label is not sown 100% symmetrically.
The top end of the zip is of poor quality and its edges are a bit sharp and not smoothened out, so you need to chisel them down a bit to stop it from irritating your chin.
From the back it looks fine.
Wobbly logo.
Pockets from the inside are sewm with a line seam. This is obviously a fake quality.
Inner labels are actually quite decent.
As mentioned previously, the sleeves are quite well made. The material is OK but its noticeably worst than the real one. Its a bit thinner and not as airy. The cut of the top at the waist is also probably more oversized than the real one. It definitely may had cut its elasticity at the waist, making it a lesser tuck to the waist and giving it a worst fit when compared to the real N98s.
Overall for a fraction of the price, its decent and looks OK from a distance. Just don't expect it to be perfect.