I've just added native in-article ads to my site.
I like the look of them, and by allowing Google to use the best colours etc I'm hoping they suit the pages properly.
One reason I like these type of ads is that the sizes fit in with the width of the device being used.
On say a desktop or laptop I like wider ads, but, if that same ad shows on a mobile, then the page widens out to accommodate it, which doesn't look good. On the other hand, if I use a size of ad that is perfect for mobile devices, they don't necessarily look right on a wider page.
By using responsive ads, this is all automatically taken care of.