Which Format of Feeds?

I am looking at using an extension to help with importing feeds in to my Opencart Site (1.5.1.3)

Which format of feeds is the most preferable to use? CSV or XML

I need to know which extension to go for as they are sold separately.

If any one can advise/give their views it would be great. Both are supported by my Affiliate Networks.

Thanks,
Rich

It pretty much down to personal preference.

If you are manually creating the import feed, then CSV would be easier to create via a spreadsheet program