XDCAM is a GOP format structure. ProRes is an individual frame format. This lessens the load on the system, as GOP formats are processor intensive. It also makes renders and exports occur faster.
I would go with ProRes 422 hq
1440 x 1080 is 1920 x 1080 squashed. FCP will play it as the proper aspect ratio and you will be just fine.
Hope this helps and best of luck.
Stephen Smith
Utah Video Productions
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