My company is going through exactly this scenario right now. We launched on and use Rails for most stuff, but there are a couple of important cases where we hav

My company is going through exactly this scenario right now. We launched on and use Rails for most stuff, but there are a couple of important cases where we have to do direct sql. Though I've had to work around some of Rails defaults for my use cases, there is no doubt that without it we'd not have been able to launch and iterate so quickly.