Onlocation gives you the ability to monitor your shoot with a calibrated screen (unlike an on camera LCD) and all the scopes you need to ensure that your footage is the best it can be - there's also focus/exposure assist and good timelapse functions too
The biggest advantage though is that you can go straight from shooting to editing - no hour long wait per tape
The only disadvantage that I can think of is that you have to have a notebook with you when you use it
What about on HD recording especially with P2 cameras?Which file extension On-location use for recording?avi?
No quality loss even if its not recording .mxf?
It can record to .AVI or to .MOV (Quicktime movies). The recorded footage and audio quality is identical to that which would have been recorded on the P2 cards.