The XM9 is a wonderful product. One of the great things about this product is it's flexibility. It is available as a 2-way or 3-way crossover with crossover frequencies between 20-5000Hz. The unit is also available in a number of forms: fully assembled; EZ kit; and full kit. If you have any skill at all, the EZ kit is easy to assemble and will save you $200.
The unit is available with upgraded op-amps (highly recommended), and balanced. Marchand will also entertain further modifications to its unit. In addition to the upgraded op-amps and balancing, I substituted attenuators for the pots for more precise control and had a baffle step compensation circuit added to the unit. Since I am using the XM9 with Marchand's passive preamp, the PR41, I also had 15 db of gain added to the XM9. My two-way XM9 has performed flawlessly and with absolutely no noise. I've used this unit with very high quality gear and the crossover has never revealed itself by noise or otherwise failed to perform to the highest standards. I highly recommend this unit for its quality of construction and flexibility.

Quality Parts. Direct support from owner/designer Phil Marchand. An excellent Crossover.

In kit form, it does take some time.

I have the deluxe version of this crossover which included better op-amps and better RCAs. I would recommend this as it is not much more money. I especially like the quality of parts used. I did have one part ship broken, but with one call Phil Marchand himself sent out replacement parts.

The cool thing is you can change the x-over frequency by replacing a small plug with 4 resistors on it. These cost next to nothing, so I bought a few and experimented.

The downside is it took me about 12 hours to build this...and I am no stranger to soldering. The directions were fairly clear, but the very sparse pictures made one part a little vague so it took several extra hours with a multitester to figure it out.
I would recommend the EZ kit, which should cut this time in half. For $50 I would go that route, as all the tedious parts are done for you.

If you don't want to build one?...buy it built. Even at the assebled cost, it is far better than anything else I have seen.