I've been using a crossover of my own design four subwoofers for a very long time now. That LR, 4th order filter is the way to go, as far as filters go. I haven't heard this particular Xover unit but it appears to be designed very well and it is well thought out. Price is very fair, too!
Biamping adds a new dimension to sound quality and once I went down that path years ago, I never came back. It is expensive but the improvement in sound quality is well worth it. Gosh, even average amplifiers sound so much better when biamped.
When biamping, active crossovers is the only real way to do it unless you want to fake an inductor by using a capacitor. However, single pole, passive filters for biamping do work well, if a single pole filter is your goal. But don't expect the performance you get with a 4th order LR filter and one really can't do that passively while driving a high impedance.
Biamping adds a new dimension to sound quality and once I went down that path years ago, I never came back. It is expensive but the improvement in sound quality is well worth it. Gosh, even average amplifiers sound so much better when biamped.
When biamping, active crossovers is the only real way to do it unless you want to fake an inductor by using a capacitor. However, single pole, passive filters for biamping do work well, if a single pole filter is your goal. But don't expect the performance you get with a 4th order LR filter and one really can't do that passively while driving a high impedance.