Upgrading to MySQL 5.6, benefits to switching to GTID replication? We have the most basic of MySQL replication setups, a single Master doing statement-based replication to a single Slave, a 90/10 mix of innodb/myisam tables. Both run Percona MySQL 5.5 at the moment but we are upgrading to 5.6 in a couple weeks and have scheduled downtime.

Will this kind of setup see much benefit by switching to GTID replication? Do I need to switch to row-based replication as well?

Trying to decide if it is worth the extra downtime for converting to and testing GTID right now.
I would say that you benefit from future proofing your environment, because inevitably you will want to add more slaves.

I also don't like having to remember specific coordinates of what statements have applied/haven't when doing a restore.  Having the server know the current set of applied statements is very useful to prevent duplicate processing/rogue corruption.  In 5.7 mysqlbinlog even has a --idempotent mode.

Operationally GTIDs are much easier to manage, and are the future :)

I recommend row-based replication as well - I think it's a great option:
http://www.tocker.ca/2013/09/04/row-based-replication.html