The critical thing with either is DON"T BUY CHEAP THIRD PARTY LENS!
The key here is avoiding "cheap." Beware that the OEM (Canon, Nikon, et al) put some pretty cheap and shoddy lenses on their gear under the rubric of "kits."

To say third party lenses are to be avoided in the mien is a mistake. There are some very fine and highly rated/regarded lenses make by Tamron, Tokina and Sigma. Do your research.