Biamping -- any good?

I have a pair of Magnepan MGIIIA's that I want to bi-amp using the Magnepan supplied passive crossover. The configuration is as follows: preamp out to passive crossover, midrange/tweeter out to mid/tweet amp directly to mid/tweet connection on speaker. Bass out to bass amp to crossover(standard outboard Magnepan crossover) to bass input on speaker. This is the recommended Magnepan setup, also providing correct resistance in first passive crossover for mid/tweet and disconnecting mid/tweet capacitors in second crossover where bass amp is coming in. Anyone have any experience/knowledge of results? I am using two Krell KSA-50s to run. Thanks

The following is from B&W tech support is response to my question about BiAmping the B&W 801 & 802 speakers. "We did not make an external crossover for the Matrix series for use with bi-amping. Once again, bi-amping with an external crossover changes the characteristics of the speaker outside of B&W's design, effecting performance and voiding the warranty (and can cause damage if not done properly).

Is there any harm in using 2 identical amps to power the high and low section of a speaker already set up to be bi-wired. It was explained to me that this was simply the next step up from bi-wiring from a single amp.

Unless you have electronic crossovers, or just need an extension of your manhood, spare the costs and put it into a better single amp.

Bi-amping works well if speaker is designed for it. Works the least well using passive cross-over and best with active 24 db/octave. I currently run a tri-amp system that I am very pleased with. I recommend a 4:2:1 ratio for woofer:mid:tweeter amps. Getting the coils out the crossover reduces phase shift and gives a much clearer image. The direct connection to the amplifier makes the sound much crisper. The down side is 1) the drivers are defenseless from rogue transients. 2) A veritable wiring nightmare. 3) A lot more tweaking is required to optimize the sound. (some people think this is fun!) Most people doing this sort of thing are speaker builders rolling their own. Passive cross-over design is complicated and the engineering is usually what you pay for in high end speakers. You can circumvent the cost by buying "high end" drivers (Scan-speak, Dynaudio, Focal etc), building your own cabinets and investing in extra amps and electronic cross-overs. Gentleman, start your multi-amping!