Just in case you're looking for a fixed-focus light with a perfect spot-to-flood pattern, I'd recommend Malkoff's M60/M30 modules with the F (flood) optic. In my experience, this is one of the best throw/flood compromise beams out there, and is PERFECTLY seamless from its gorgeous spill to its smooth hotspot. Mind you it doesn't excel in throw (too much light is directed to the spill), nor is it perfect in flood (strangely, the hotspot ends up feeling a little too narrow).
Of course, the ideal solution to having the best flood/throw I've found is to use a SureFire C2 (any comparable model would do) with an FM34 flip-up diffuser. You can go from an unobstructed throwy beam to perfect, wide flood in half a second, and back again just as fast. Of course, I suppose that doesn't meet the "full range" of flood to throw you mention, as it's either one or the other... But it's better at the extremes than any focusing light I've ever used.