I have been putting some hours on these speakers since completing them and maybe my ears are not good judges but, damn, does the RS28A-4 tweeters sound excellent! \n\nIs this just me? I have been really putting some hours on these and there was no user break-in period needed, or realized. I loved these speakers the moment I turned them on. I was skeptical choosing a design with an aluminum tweeter. Seems there are some die hard biases with regard to soft dome or metal dome tweeter preferences. I figured I'd be more of a soft dome type. I am easy to please in the higher treble ranges, as long as it doesn't grate my eardrums. I'm usually ok, and never really took notice of which I preferred, or, if that's just another one of those audiophool, self-inflicted preferences. \n\nEither way, this metal tweeter has to be the exception to that bias.