Anyone using Orchard in combination with MySQL?

How is the performance?

I tried one of our 'migrate' commands : on MSSQL2008R2 it took around an hour, MySQL had an ETA of 4 hours+ (I canceled it then) and doesn't give me hope it'll match the MSSQLServer performance :/

I use an Amazon RDS MySql instance for a number of my websites and it works great, but I don't have numbers that would help you.  I'm also not doing a lot of massive data migrations.  For what I'm doing though it's great.