Which sounds better 2 way or 3 way speaker design

Don't dismiss 4 ways. 

Some excellent info here from the people who know and some really dumb info from the people who have no idea what they are talking about.

That being said, none of the speakers you are looking at would be on my short list especially for $18K!  But that is me.  Go listen to the Revival and new PMC speakers for comparison.

We have modified speakers for 25 years for customers.  What I can advise you is that drivers and cross-overs are important.  We placed Accton drivers in an old Infinity Kappa speaker and built external X-overs and that dumb experiment would beat most people's speakers they have heard or own.  GO figure.

We also prefer Field Cold speaker designs for comparison.

Happy Listening.

Woofers begin to break up in the upper mid range whereas tweeters often have a resonance peak and power handling problems in the lower high frequencies. That said, I heard some JBL 2 ways, a CD and 15" woofer, netherless, they blended  well together and the sound was far superior to the 4 ways I've owned.

 There are no set rules - just guides.

I’d rather own a nice 2 way over a crappy 3 way and vice versa! I use my ears and pocketbook as the final arbiter.

@toddalin 

I said ~80 Hz for the bottom of the midrange because the idea is to keep at least the fundamentals of the human voice within one driver and there are those who can certainly sing lower than that.

100% agree with this. Having the fundamental frequencies of vocal range produced by a single driver offers better coherency than splitting it between a woofer and midbass/midrange driver.  Of all the speakers I’ve designed, this philosophy sounds best to me. There are always other factors, but this makes more sense to me than installing a crossover in the middle of the vocal region… the vast majority of instruments also play in the same range, so it affects a lot of music. YG Acoustics offers some models that use similar logic.