Well, no. Yes, a bit more expensive to buy, but not more expensive TCO if they were actually on a lot, at least for the low-voltage versions.

And also, obviously not hotter, how could they be more efficient at producing light, and still be hotter? Yes, the filament in halogen lamps is running hotter, that's why they are more efficient (and the halogen process is what keeps the filament intact despite the high temperature), but they're also more compact--the total amount of thermal power produced by a halogen lamp of equal light output as a regular incandescent bulb is lower, and thus, if you put it into the same form factor and under the same cooling conditions, it's actually going to be cooler at the surface.