I like inline-styles while designing in-browser since I don't have to go back and remove selectors that I don't end up using. It's also quicker for me to see what styles are applied to what and from where. I actually have never run into problems leaving them like that for one-off styles (e.g., if I need a custom padding on one specific DIV) until I need to customize these styles for mobile in which case I'll have to remove some so I can override them with my media-queries. But, if I end up using the same set of rules on multiple items I almost always create a class for it. So - in a nut shell, I use them for one-offs that I don't need to override using media queries.
As a disclaimer, this is my opinion based on my years of experience and not necessarily based on best practice. If I'm coming into a project I will always try to use their established best practices, which is typically not to use inline-styles, although they do make my life easier both as the initial developer and as the later maintainer.