Welcome to Android Central! The stock Internet browser is typically leaner than Chrome, and so it might be a bit faster. However, I don't think Samsung's Internet browser syncs bookmarks with your desktop Chrome, so you have to create your own bookmarks. That can be a hassle, especially if you want to transfer those bookmarks elsewhere. Chrome syncs all of your bookmarks from your desktop Chrome browser, so that's a big convenience factor for me.
If you have a limited data plan, Chrome also has a nice feature that allows you to conserve data by compressing the page on the server side first before downloading it (much like the Opera browser does). I don't think the Internet browser has that feature.