Hey Doug,
Sorry for the delayed response.
Both options will work. but i would suggest using the push in toilet flange. Much easier and can be installed after tile is placed, which is ideal for a toilet seal.
They work great on copper as well. They come in 3″ and 4″ sizes
Here’s the 3″ – https://amzn.to/2shpgGO
and a 4″ with the tightening bolts – https://amzn.to/2shfIfi
Let us know how you made out
steve