Even if not suited for ongoing use, are these products not valuable as a tool?

When someone builds a DIY crossover/filter arrangment, usually the resistor/capacitor values will be fixed - and one has to decide if any filtering will be needed in addition to the basic crossover functions. Because of their flexibility, using one of the Behringer products for an evaluation of choices may be useful. Once one has made the determination, 'this is what I want the active electronics to do', then a DIY circuit can be the next step.

Of course, if you are replacing a passive crossover network with an active crossover, and you already know the target crossover points and voicing needed, you may not need an 'experimental platform', both with regard to active electronics or acoustical measurement.

I guess is somebody has the money, then using the Behringer as an "evaluation tool" might make sense. It seems though to me to be an answer to a question nobody asked, since in most cases, the crossover frequency is a known value, and any tweaking is best done by an external analog EQ in any event.