I found Babylon to be on par with THREE on all the areas I needed, except for Camera control where Babylon really shines with it’s built in support for many different types.
Looking at npmjs.com, it’s clear that THREE today the ‘go to library’ when doing 3D in the browser. Currently THREE has 304k downloads a week, while Babylon.js has less than 6k of downloads a week, clearly THREE is more popular.
Size wise, I have not done any test on the produced bundle. I find this absurd in today’s world, where a website does a million AJAX request to load commercials anyway…
The only reason I recommend THREE over Babylon.js is because of it’s popularity on npm. Else, go with any library - they both solve the three-dimensional problem equally well in my opinion.