Sealed bookshelfs

I currently have the original NHT Super 1’s in my system which I mate with an ACI Titan. I would like to upgrade the speakers by auditioning 3 different bookshelf speakers in my home. The NHT Classic 3’s are on my list and was looking for recommendations for other sealed speakers or Speakers which come designed for port blocks like Ascend's Sierra.

Thanks for the help,

Bob