I use MariaDB on all of my websites these days, the largest of which tops out at around 5K queries a second. The biggest draw for me was the XtraDB engine (which is also found in Percona Server) which is a replacement for InnoDB. XtraDB performs much better on SSDs and I was able to get over 50% performance gains on some queries with the default settings. This may or may not be applicable to your specific environment, but it is a drop-in replacement so it's very easy to just install it on a test box and stress test it with your current code.