Is there a difference, other than bundles are inline with your other emails and categories are accessed in separate tabs?

I for example have all promo emails "queue" up whenever they come in and show up at 9am every day.

I have all "low priority" emails show up at 5pm when I'm winding down my workday to deal with them.

That's the kind of thing I'm going to miss the most.

You cannot create custom categories, you're limited to the 5 options Gmail provides you.

You can't archive all in one swipe.