Exporting high quality FCPX project for upload.

Hi everyone.

I'm a FCP X beginner with some questions on how to deliver a project in the way it's wanted....

I've been asked to deliver a version of my current project that's as high quality as possible (although just for viewing, not editing, I think). They haven't asked for any particular format, but they've said they want split audio. I will need to share the project with them by uploading the video to the web and use a file sharing system to give them access to it. The end use of the video is online viewing.

I'm shooting in AVCHD, and I'm editing using FCP X.

Since I check 'create optimised media' when importing my clips, I think FCP X is converting them to Prores 422 (is this right?)

My questions:
1. What FCP X export settings should I use to get a high quality project with split audio (the project has a music bed and interview audio, which I guess they want to be able to alter separately) that won't take a lifetime to upload?
2. Once the project has been exported, is it ready to upload? (or are there other steps I need to take first?)
3. Any tips on minimizing uploading times while maximising project quality?

Any tips/advice about anything relevant to what I'm trying to do will be super welcome!!!

THANKS
sarah