I was about to send this post, but just then I was notified of new reply being posted. Upon reading Dennis's response I see that mine is now redundant, but since it took me a while to type it, I will post it anyway, if I may:
Mine is certainly a layman's opinion, but from what I have read (and that includes Jim's and Dennis's comments), and if I remember correctly, ribbon tweeters, like RAAL, do not have quite as good a vertical off-axis response as dome tweeters, but at the same time have a better horizontal off-axis response. If that is so, then I believe we could say that as long as one listens while sitting with their ears fairly closely aligned in height with the height of the tweeters (as I suppose is best for getting most out of the listening experience, anyway), then when not sitting in or near the sweet spot one should be able to get more out of speakers equipped with ribbon tweeters than ones with dome tweeters, all else fairly equal.
Of course, this is strictly speaking with reference to horizontal off-axis response and sitting farther away from the sweet spot. No judgment as to what kind of tweeter is "better" overall. After all, I suppose a well-made tweeter is exactly that, regardless of the type, and the rest is up to the individual to decide what pros and cons of any design and model best suit their needs and tastes.
Ivan