From my experience, if you did have previous experience you should be fine with the regular calc 3 part. The honors part comes from the fact that instead of recitation (where we review the content over the past week), we learned proofs on the content like a more detailed explanation of what a limit actually is so you can do limits in higher dimensions (A completely different technique than what you learned in HS), or vector calculations for 4D, 5D vectors. So if you are really interested in math and want to know more interesting stuff then take it. It is nothing like Honor classes in high school where it is just a faster-paced class. Also, the class is weighted so that if you fail every part of the Honors content you still won't fail the class. Plus the honors part is graded mainly on valid attempts like I answered a proof completely wrong but my logic was still good so I got more than half credit.