Please note this is more of an observation applying the dust tool rather than any kind of in-depth review:
Capture One is certainly lots faster than Lightroom. Alas, for me, speed at the unacceptable sacrifice of quality. My photography involves lots of rough travel which involved lots of sensor dust. With Lightroom I could fix the dust in one image, batch apply (wait all night) and hey presto - all fixed. Try this with Capture One - hey presto, about half fixed. The other half with resultant 'tool mark' blobs worse than the original dust.
So, for dust fixes this product is no good. Phase One need to fix this, I'm sure it's an important tool for many. Though, in fairness, this software is aimed more towards the Studio phoographer, where the environment is a little cleaner!