I'd never really seen them as a viable alternative to a telescopic pole and 95% of my work can be done with the trusty CLX-22.
However, just lately I've picked up some normalish work with a couple of high three story windows, a few rooflights with difficult angle access and some solar panels, so a pole around 45 feet + would be useful. Nice point about the modular is short sections for ease of storage and carrying and the ability to add too as well.