So let us start first what is a third party camera lens, a third party camera lens is one that has been developed by a different company in which you are using of a different brand of camera. For example you are using a Nikon or Canon Camera, and then you are using a Sigma or Tamron as a camera lens for your camera.
Mainly the reason that most photographers or other camera enthusiasts purchase these lenses is because it is more cost effective for them. Now let us discus what may be the advantages or disadvantages of having this type of camera lens.
What are the Advantages?
First off is that third party camera lens are a lot cheaper than the branded camera lenses. Second is providing excellent image quality, where can you find a camera lens for example Tamron which provides excellent image quality as well as a lot cheaper than Nikon and Canon. Lastly some brands like Nikon or Canon models which do not sell some specific lenses are mostly can be found in generic brand lenses such as Tamron or Sigma.
What are the Disadvantages?
First is quality is still the issue, no matter how cheap the generic brand is what's important is the quality it gives you, meaning the durability of the lens. If you do intend to resell or upgrade your lens in the future. Generic brands do not hold their value not like Canon or Nikon. There is no guarantee that the generic lens you buy will be compatible with any Nikon or Canon EOS camera. It is always best to really look into this fully before purchasing a third party lens, and do not simply presume because the salesperson which is by the way paid by a commission always says it is compatible and they will add that it will fully work with your particular digital camera, and that there will be any problems encountered. Lastly, there are third party lenses do not have an option of turning on fully manual modes. They also do not offer extra features such as Canon USM for fast focusing.
What you should do?
In any way, you cannot interchange that Nikon Camera Lens if for Nikon Camera and Canon Camera Lens is for Canon Camera, but if you will consider the money involved you might want to think otherwise. Eventually what you think is the best fit for you is the best thing that matters.