I think this one is f2. Yet the over-saturated color comes from the E100VS slide film, not the HC50/f2 itself.
This one, on the contrary, is a badly scanned file from an f2 shot. The original color on the E100GX slide film looks twice as much saturated as you're seeing on the monitor....
The HC50/f2 is sharp at wide open, as with most CV lenses. The color rendition, IMHO, is a bit "stiff" and "cold" compared to Leica lenses. Not in a bad way though.