The main Pro now is one has to use it for Android dev. The main con is many other tools still use Eclipse. Even Appium automated test framework for Android.
Nowadays one must use Android Studio. It has great features such as code search: one can context click on
Find Usages
when a class is highlighted and find uses in the code. (nevermind the word "usages" is incorrect English. :-) It's the Google way. Swim with it.
It has some tighter integration than was accomplished with Eclipsed such as the nice feature to context menu on an xml layout file and find where in code it is used. Useful.
Also, it uses Gradle so people can write their own build processes rather than having an IDE do it automatically. I think this frees Google from having to waste time figuring out how to make the IDE handle all the configuration mess.
While our build went from 2+ minutes with AS 1.x to 17 minutes with AS 2.x, this could be attributable to how we have our Gradle files laid out. We need a build programmer to make sure our build configuration is correct.
As you can see, the main Pro is one has to use it and the putative Pros are it has better support for Android code navigation and screen designers. The main Con is it moves from the standard IDE used for most all other Java development and it doesn't provide drastic improvements in performance. Another Con is it arguably introduces the need for a new role of build engineer; but many projects already were bogged down into manual build definitions with Maven; so, that may not be a Con depending on your team's speed.