Agreed...although I've got my preferences and invoked the name of a specific driver to clarify that, I don't want us to drift into a 'cable/interconnect' style pull-pull this vs. that arm wrestling match. And I'm infamous for off-topic drift....
There's stellar examples of all types of tweet designs, granted. And the design and engineering of all and the compromises that come with the pursuit of excellence of any driver at this point are, as timlub points out, pretty well canon. And the matching of tweeter A to woofer Z reminds me of human marriages; some you understand, others...*shrug*....you shake your head and walk away....*G*
Eric invokes design principles, which is what I interpreted Eric had opened this forum over and about. Like most things, it's difficult to stay on 'theory' without the mention of particular manufacturers' offerings as an example, because that's what we know in the specific...and cite...
IMHO...it's become hard to stay on topic within any discussion about Anything of late, whether it's tweeter design, cars, underwear, or *deep breath & 10' pole* politics...;)
If I wanted to throw gasoline onto 'this fire', I Could point out my personal pursuits of DIY Walsh speakers. I would hope that might take us into a discussion of Real Esoteria, say plasma or even dustier corners of the audio reproduction realm. But would that take us off topic even further?
Perhaps.....
But, in review of the original query by Eric, our OP, I interpret it to mean 'what do you like and why?' without descent into a 'turf war' over it.
OK...I like my ribbons. I like my Walsh's better, even with their 'warts' as DIY stuff tends to have (I'm working on that...). *G*
Next.
Lets' have fun, and keep it light 'n sociable. ;)