I would advise that unless you have a very good reason to not use it, you should go with Passenger. It's way simpler to set up, less moving parts, and you don't

I would advise that unless you have a very good reason to not use it, you should go with Passenger. It's way simpler to set up, less moving parts, and you don't have to worry about monitoring mongrel, configuring proxies, and all that junk. You can always change later if you discover it's not working for you, but until then go with the simplest solution that works, which is definitely Apache/Passenger. And yes, I do use a staging server, or rather a staging directory which is hooked into a "beta" url. It's an invaluable final sanity check in the production environment. That is not hard - the tricky thing will be staging on something resembling the production database, you'll have to figure out some way of doing that. Ironically, the staging environment is probably where you'll want to use mongrel, since you'll want to start the app with a different rails environment to point to your staging DB.