Are NBS cables are sound better than Nordost ?

If low end NBS then don't bother. Omega I and II are pretty good.

I suppose it all depends on the complementary gear and your tastes. In several tube-based systems I've heard them in, the Nordost speaker cables and interconnects sounded a touch bright and harmonically lean. But, this was probably a system-dependant phenomenon.

I personally like the NBS line of cables. Their different lines have a different sound, so, if you work with a dealer, you can try different cables to dial in what you are looking for. One word of caution, don't try the Black Label stuff, it will make you disappointed with almost anything else.

Other cables I personally like are: Basis (the turntable manufacturer), XLO limited, and certain Audionote (uk) cables.

Larry is absolutely right about the Black Label, we tried a lot of Power cord but none can compare. My friend have about 5 of them in his system. The solidity of the image, the body and weight, the silence. I just wish it is not as heavy and rigid and expensive. Sometimes you wouldn't use it just because it is so difficult the work with.

I made some comparisons with NBS Black Label (BL) and Nordost Valhalla and the choice was quite easy. While the Valhalla has some good detail retrieval it lacks completely body and natural weight, also it's color is withish. In the past I owned MIT cables and found them pretty good until I met NBS. MIT cables sound a bit artificial to me(boxes??).
No, the NBS BL is the far best cable I'm aware of.
BTW in Europe there is a special version which called the NBS Active series with an excellent price quality ratio.
Now I understand that NBS is the most copied cable: because it's so good. BTW I heard recently such copied NBS (Heavens Gate Audio) which is derived from the old Statement series. Well it sounded quite bad, very hard and out of balance. So be aware of such brands, they also cost money.