Thank you for the recommendation, Danny. I did check out your video on the X-On-Wall speakers. Very interesting concept. I am using bookshelf speakers as heights simply because I already owned the speakers and they were taking up space. I do not have the localization issues you point out in the video because they are well away from the listening position. I appreciate the advice. But, for now, if I was going to make appreciable improvements for my theater, I will focus on the room and not on the speakers.
Plus, the fastest path to divorce is bringing home another set of speakers...
Saying this, I was just looking for a fun project with a pair of speakers that I threw in the back of my theaters simply because I was tired of tripping over them. I have since replaced them with another set of speakers I was tripping over. I have never upgraded a pair of speakers before and have seen plenty of your videos. So, I figured, why not give it a try with the 606's. But, before I spend any money, I wanted to see if anyone else on these forums has any experience with this upgrade and their before and after impressions.