Recommendations for electronic crossover.

jpahere, I hat to be a stick in the mud but B+W does a good job designing it's cross overs. In my experience you are going to wind up pulling out your hair trying to get the system to sound right. I think you are much better off with something like a 100watt/ch Class A amp, perhaps a lightly used Pass amp. Used JC 1's would also be a great choice and because the new JC1+ is out a lot of old JC1s should show up on the market soon.

As a note to others considering this sort of approach dynamic speaker do not benefit much from bi amping and frequently wind up worse. You are much better off adding two subwoofers with both high and low pass filters. 

Sounds to me mostly like theoretically-based conjecture. Have you listened to bridged configurations to form an opinion this way?

Yes, and if you search you’ll find all the info I’ve heard/measured and found on it.
Like I said above , bridging amps makes what could be a good stereo amp, lean towards becoming a mono PA amp. As many parameters take a hit, not just the ones I’ve mentioned above.

Each and every one of us preferred the sound of the bridged configuration, with some describing the sound as now being "more hifi"

This statement says it all.
A really good amp should sound big, tight and wash over you with dynamics and detail that don't sound like it's coming from any of the the speakers drivers, and have a sound stage you feel you can get up and walk into.

@georgehifi wrote: "... bridging amps makes what could be a good amp, lean towards becoming a PA amp." 

This has been my experience as well, with some pretty nice amps (Accuphase). The difference was immediately obvious. 

Duke

@georgehifi --

Each and every one of us preferred the sound of the bridged configuration, with some describing the sound as now being "more hifi"

This statement says it all.
A really good amp should sound big, tight and wash over you with dynamics and detail that don't sound like it's coming from any of the the speakers drivers, and have a sound stage you feel you can get up and walk into.

It says what? The people in attendance of said listening session, among them musicians, knows how to use the term "hifi" in its truer sense, and nothing about the statement excludes the traits you mention, on the contrary. A smoother, more refined top end could point to better transient response (i.e.: better slew rate), and a more lively and open sound is exactly that and could involve many other parameters; like more headroom, less restricted dynamic capabilities, better sound stage, etc. The traits in particular you do mention are very much a factor of the speakers as well, I should add, so it seems me you're bending the statement to have it suit your agenda. 

In general Bridged Amps

Pros=
More watts.

Cons=
Worse damping factor
Higher output impedance (has relevance to damping factor)
Lower stability (especially into low impedance's)
Current ability is reduced (especially into low impedance's)
Higher distortion.