I finally caved and ran a proper multi-material job this week, the kind with four colours and a tidy little logo embedded in the lid. It looks lovely. It also produced a poo tower nearly as heavy as the part itself, because every colour change purges the old filament out before the new one flows clean.
That is the bit nobody puts on the marketing render. The mechanism works beautifully, the loading and unloading is reliable, the colours line up. But you pay for it in time and waste. A print that takes ninety minutes in one colour took the best part of four hours once it had to swap filaments on every layer, most of that spent priming and wiping rather than building the thing I wanted.
So is it worth it? For a one-off display piece where the look is the whole point, yes, absolutely, and I'd happily do it again. For functional parts, brackets, jigs, the endless enclosures, no. A single colour prints faster, wastes nothing, and nobody has ever asked why the cable clip isn't two-tone. I've settled on a simple rule: multi-material when the colour is the feature, one colour when the part just needs to exist. Most of what I print falls firmly in the second camp.