• Replication is not a backup policy. A mistyped DELETE statement will be replicated on the slave too, and you could end up with two, perfectly synchronized, empty databases. Replication can help protect against hardware failure though.
• Replication is not an answer to all performance problems. Although updates on the slave are more optimized than if you ran the updates normally, if you use MyISAM tables, table-locking will still occur, and databases under high-load could still struggle.
• Replication is not a guarantee that the slave will be in sync with the master at any one point in time. Even assuming the connection is always up, a busy slave may not yet have caught up with the master, so you can't simply interchange SELECT queries across master and slave servers.

Source: http://www.databasejournal.com/features/mysql/article.php/3355201/Database-Replication-in-MySQL.htm

First import mysql tables whith all users

mysql -u root -p mysql <temp/mysql.sql 

Then you can do flush privileges or use the old password. Finaly import all databases

cd /srv/temp
for i in *; do 
   db=${i%%.sql};
   echo $db;
   mysqladmin create $db --password=xxxxx;
   mysql -u root --password=xxxxxx $db <$i;
done

unfortunately in the middle the cycle failed (i caused it intentionaly)

X=0
for i in *; do
   test $X -eq 0 && mv $i $i.done;
   if [ $i = 'gld.sql' ]; then
     X=1;
   fi;
done

mysql> CHECK TABLE fixtures;
mysql> REPAIR TABLE fixtures;
mysql> REPAIR TABLE fixtures USE_FRM;

• http://felipecruz.com/repair-mysql-database.php

• http://www.mysqlperformanceblog.com