I have yet to try the last two. I really enjoy duckduckgo on my phone, but I know there was some controversy. I guess I’m lazy but I love the fire button that burns away all your open tabs and history in one click. Started using Brave recently and I kind of enjoy how it reports how much stuff its blocked and the breakdown of what it all is. I have had no noticeable issues with either one.
I guess you're talking about iOS, so yeah they had no choice, everything is Safari based there (for now). But on android, as I mentioned at my comment above, it's chromium based.