This is my take on using Capture One as an alternative to Apple's Aperture.
I have downloaded and used Capture One image editor for all of the free trial time offered by Phase One.
I had settled on using Lightroom as my Aperture replacement and had been dissatisfied by LR's unintuitive handling of images and it's inability to organize my images and make them easy to find. The editing capabilities of LR are top level. My dislike is the extra effort it takes to access and process an image and the inability to know where my original and edited images were being stored. There is a lot of moving sliders, opening modules, and waiting for things to happen. Simply uploading and importing images can be time consuming and frustrating. Similarly, exporting edited images is not a simple, quick thing to do. These are the primary reasons I decide to try CO.
CO, in my opinion, has many of the negative aspects of LR. Some procedures are more pronounced than LR in their need for tweaking and tuning in order to carry out some processing function. I watched a video which was supposed to train me how to organize my images 3 or 4 times. Maybe I am a dunce? I was never able to create a catalog which had a structure that would intuitively allow me to know where my images were and to be able find those images weeks or months later. I think the CO RAW editor handles my Canon RAW images in a way which produces image colors which I felt were not accurate and required more extra processing than they should have. CO requires a lot of mouse/trackpad action to carry the image from import to exporting the final edited picture. Though it may be possible (not by me) to create a preset to accomplish many functions. I found CO too complicated and too full of links, boxes to check, and sliders to slide to be of use to me. The DAM aspect was nonexistent. Smart Albums are useful to organize small or exclusive groups of images, but there is no way to organize those albums leaving you with questions about where any giving image is located.
On the positive side CO purports to handle key words in a different and, possible better way by utilizing a keyword library. If you can learn how to use it I think it would be very handy. As mention earlier the ability to create presets could be a decided link clicking and time saving asset if you can master the preset creation process.