You don't "lose" your adjustments; they're essentially proprietary and still exist in Aperture, or Photos if you migrate. NO software can reproduce those completely; the only way is to export TIFFs. Capture One can import lots of 'em, but not all. As even Capture One used to note, their adjustments are better than Aperture's, so perhaps it's better to start over from RAW. Here's what they say transfers directly:
Below is a list of what is supported
Collections
Aperture Project -> Capture One Project
Aperture Folder -> Capture One Group
Aperture Album -> Capture One Album
Any Aperture Projects which directly contain images have a generic sub-album created in CO to contain the images.
Smart Albums, Books, Light Tables, Slideshows, Web Journals, and Web Pages are not imported.
Adjustments
- Straightening
- Crop (if not Straightened)
- Flip
- Black & White
- Enhance/Definition -> Capture One Clarity
- Enhance/Saturation -> Capture One Saturation
- Exposure/Exposure -> Capture One Exposure
- Exposure/Brightness -> Capture One Brightness
- Highlights & Shadows (Mid Contrast ignored)
Everything else is ignored.
Metadata
Star Rating
Color Label (note: Ap Grey becomes Capture One Purple)
Applied Keywords (flat, not hierarchical)
IPTC Core Contact: Creator Name, Job Title, Address, City, State/Province, Postal Code, Country, Telephone, Email, Website
IPTC Core Content: Headline, Caption, Keywords, IPTC Subject Code, Caption/Description Writer
IPTC Core Image: Intellectual Genre, IPTC Scene Code, Location, City, State/Province, Country, ISO Country Code
IPTC Core Status: Title, Job Identifier, Instructions, Provider (Credit Line), Source, Copyright, Usage Terms
Whether it's "better" than Lr, or "Mac-like" or useful or worth the price depends on what your own personal opinion, but worth looking at. And I think there might be a workaround for hierarchical keywords somehow; C1P finally got around to supporting them (poorly, but improving). And missing lots of IPTC stuff, but again I think that may be fixed with workarounds.
I'd recommend a look at Mylio, and even Aperture Exporter. At least the latter gets you set up to move to most any other organizer.