As someone who loves vertical tabs, I was disappointed with Vivaldi's vertical tab behavior/implementation compared to Edge and Brave. I used Vivaldi full time for half a year before deciding to revert back to Edge for work and Brave for personal.

Of course you can customize with CSS and other types of things, but I'd ideally like my browser to just work well and be designed well.

Having said that, I miss some features from Vivaldi. However, I am much happier using vertical tabs in other browsers that have that feature.

tried vivaldi and it felt really bloated and clunky to me, atleast compared to zen, is that just how it is or is it much better after configuration?

Orion, too.

And Brave

Firefox's new implementation is subpar. You're better off using an add-on like Sidebery for more features, but you need custom user chrome CSS to hide the horizontal tabs.

I really don't see many similarities between Orion and Arc but I also didn't use Arc very much because I was pessimistic that it would stay free and consistently updated without annoying monetization features. I didn't expect them to switch to a brand new browser though lol.