Automated Backup Solution for 2TB data on macbook pro

I will soon have a macbook pro with an external LaCie 2big Quadra in a RAID 0 configuration (2X 1TB) connected via a 2 port eSata xpress card.

The external drive will contain critical data that I can't afford to lose (sample libraries, audio projects) so I need a backup solution.

I need a solution that provides the following features:

- The firewire bus on the MBP needs to be completely free for exlusive use by my audio interface.
- I need to backup both the external drive and my system drive on my MacBook Pro.
- I need to be able to schedule the backup to run automatically during times when I'm not using the laptop (ie in the middle of the night).
- It must have minimal impact on the performance of my system when I'm using it.
- The backup must complete in a reasonable amount of time (I doubt it's if it's feasible to back up around 2TB of data with a NAS but I could be completely wrong here).

Does anybody have any recommendations both on the hardware and software side?

As a firewire drive is not an option I would have to connect the backup drive either via USB, the 2nd eSata port or the Ethernet port.

How feasible is it to back up 2TB of data using these methods?

Could incremental backups be done via wireless NAS?

All suggestions welcome.

Hubie