Bi-wiring/Bi-amping...worth the fuss and expense?

Does bi-wiring and/or bi-amping justify the added expense of additional cable and/or amp? If so, why don't all speaker manufacturers (like Dynaudio) provide this capability? Assuming it does, is bi-amping meaningfully better than bi-wiring?
On some speakers its easy to hear the improvement and on others not at all. I have not thought that much of bi-wiring most of the speakers I have owned so far. I have bi-amped before and thought it was a big improvement when done right (not easy or cheap to do}. I would like to try it again one of these days with the system I have now.
Bi-amping can definitely make sense. Whether it'll make a difference depends on the load your speakers present and the quality of your amplifier.

Very few people bi-amp, however, so speaker manufacturers, especially at the low end, may not feel the need to accommodate the few who do.

Biwiring has the virtue that it's a lot cheaper than bi-amping. On the other hand, it's pretty much indisputable that two cables deliver exactly the same signal to the speaker as one cable. Nevertheless, some people report that this signal sounds different. You decide.

Bi-amping does make sense. Whether it'll make a difference depends on the load your speakers present and the quality of your amplifier.
It all depends on the speakers and amps involved (as well as listening room size). A more specific answer would need to know these variables.

The advantages of bi-wiring may be situational, but to say that each wire delivers the same signal is misinformed or disingenuous about the arguments put forth in favor of bi-wiring - about which many people disagree.

The main argument is that having separate wires for highs and lows carries different signals back from the *speakers*, i.e., back EMF. It doesn't have to do so much with carrying different signals from the *amp* in question.

The Vandersteen site has one of the more concise faq entries on this subject.
I have the Dunlavy SC-5(s) and vertically bi-amp and, of course, bi-wire. This speaker design is very current hungry and equipment picky. There is a substantial difference in
dynamics and low bass performance I believe in the bi-amp arrangement.
Hi! My opinion? Well, bi-amping can be great with certain speakers, but makes little difference with others. Same holds true with bi-wiring - perhaps B&W being a rare "must" even by their own recommendation. Don't forget that some wire mfgs. offer a split wire in one sheath which isn't true bi-wire but is close and less expensive. If you do a true bi-wire meaning 2 seperate runs of wire, remember that you should use better wire for the tweeter/midrange and can use less expensive for the bass, but be careful of how you make this match since a mismatch can lead to some weird phase problems. I think that the best solution for most speakers is to get a great amp and pair it to the most expensive speaker wire in a single run that you can afford. This will sound better than bi-wire or bi-amp. Look for a pair of Transparent Ref. wires or Transparent XL or MIT Oracles. I have auditioned a lot of wires and still think these two companies are the best.
What about going with Mono Block?...Does going with Mono Block with Bi-Wiring Sound better that running with two amps
in Vertical Bi-amp mode?
In my experience the more you split up the music signal between different cables, amps, drivers, etc the more disconnected the music sounds. Sure you hear more apparant detail, soundstage etc. but the music's message gets lost.

That is a very good question. I spoke to John Dunlavy some
time back and he defintely supports the mono option. My personal experience has convinced me that the vertical bi-amping approach can have it's advantages. The real issues
deal with current v. distortion. If the speakers thrive on high current reserves than the vertical option may be better. In doing this, however, the cumulative distortion
and noise is doubled. Probably for most the mono option
would be better unless you have really clean amps. As always, it depends!
Thanks Orest1 and Brauser, I will give the Mono-amp with bi-wiring a try when I have the $$$..:-). I'm thinking of the Pass Lab X600(used) and/or the Odyssey Mono Block(new). In the meantime, I'm currently vertically bi-amping two s200 with an S100 preamp driving the Sony SS-M9ED speakers. Will this setup sound better if I just use 1 amp in regular bi-amp mode?

Bi-wiring doesn't work
If you have speakers that accept bi-wiring
You must try simply the MS-2 bi-wiring kit set of 4 small cables to bridge and it is another world.....
After biwiring my Nautilus 804s I immediately felt the floor shaking from lower bass frequency enhancement.I no longer have any desire for a subwoofer.