The best feature is being able to use Firefox extensions and thus uBlock Origin and sponsorblock on iOS. It's a little buggy but worth it for me.
While uBlock Origin can be installed in Orion on iOS just fine, it remains non-functional.
As discussed before, I find this to be false advertising by Kagi: https://news.ycombinator.com/item?id=48476448
Next best thing for me is using Safari with uBlock Origin Lite, which actually works.