Update: These are way better than the 737s with Audax tweeters I had last summer. I stand corrected. The tweeters in the current 737Rs aren't merely Mission badged Vifas, they're Mission designed and manufactured.
737s I had in June of 2010, and have what appear to be Mission badged Vifa tweeters, not Audax. I am loving them right now, perhaps more than those. I'll have more to say soon, as I've the Audax and Vifa tweeters in completely different systems lately (the Audax/Polydax in the Enigmas, the Vifas in a set of newer Angstrom monitors I haven't told you about, because they're from the 90s).