Auto Increment vs. UUIDs

How well does Percona XtraDB Cluster support UUIDs for primary keys?

PXC does no change to the way MySQL generates UUIDs, and from the general concept, a UUID should be 100% unique between the nodes, as part of if is based on hardware uniqueness, like the eth card MAC.
See here for more details:
https://www.percona.com/blog/2014/12/19/store-uuid-optimized-way/
http://dev.mysql.com/doc/refman/5.6/en/miscellaneous-functions.html#function_uuid