Con RAM usage
The high performance and speed come at a cost of an abnormally large RAM usage when it comes to Chrome. This isn't a problem with machines with lots of RAM (4GB+) but it's very noticeable with computers that have less RAM than that and can slow it down a lot depending on the number of open tabs.
Con Heavily tied to Google's ecosystem
While it's possible to forego logging into Chrome via a Google account, the browser is designed to be used with a Google account in mind. A Google account is required to sync bookmarks, passwords, history, open tabs and settings for both the browser itself as well as extensions and apps across instances of Chrome both on mobile and desktop.