That seems a very specific use-case rather than the general use purposes I was speaking of; in your example non-manifold geometry may be a problem, I've never worked with either. For uses other than what you've mentioned, unimesh vs multiple pieces may not matter as much or at all. In the example I used of baking to normal maps; generally speaking you're likely to be baking your high-poly multi-piece geometry to a lower poly unimesh model if you were modeling it for that purpose, so I don't think you can discount "normal maps" even if the end use may by fitting room so I don't feel you can discount that either.

I feel you may only looking at this with a very a narrow view of uses for something like this, and trying define "better" for all cases using solely that view, when it may not be the case.

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