I have the platinum 16. It is the same as the HQ 16, just a little different style and a couple less bells and whistles.
I bought the HQ sure foot and installed it on the machine to use with rulers. Had no issues doing this. I like the machine and have no problems with it. She will use any thread I put in her. Last quilt I used her for was a King.
I have purchased several HQ rulers. If I have any ?'s I look at the HQ 16 videos. I love my machine.