There are many things to consider when answering this question and it all depends on your life and that of your fiancé or fiancée. Many people think that the K-1 visa is the only way. Sometimes it is the best way or only way if you are not willing to marry the person and have him or her process an immigrant visa in another country. But if marriage is an option before coming to the United States, then the immigrant visa and K-3 visa become relevant to the conversation.
As of the date of this posting, the K-3 visa is not as relevant because processing times for the immigrant visa are relatively short compared to what they were in the past.
Talk with a lawyer to help make the best choice.
If you have any questions regarding immigration, please feel free to call me, immigration lawyer Shawn Mesa, at (813) 679-5780.
Disclaimer: This information is provided as a public service and not intended to establish an attorney-client relationship. Any reliance on this information is taken at your own risk.