Migrating MyISAM tables from 5.5 => 5.6

Question

I was wondering if anyone had any pointers on migrating MyIASM tables from mysql 5.5 to 5.6, specifically using Percona builds, via an rsync?

Is this safe?

I know we need to do a full mysqldump/reload for a migration for InnoDB tables but I didn't see any notes about significant changes to the MyISAM format between the two.

It would make things a little nicer for a rather large MyISAM db that would take several days to complete with a mysqldump.