Maximum (realistic) sizes for OVA/OVF format and export?

Hi- has anyone hit any problems with exporting large (e.g. > 1TB) VMs in OVA/OVF format?

I realise that you can split the files generated, but leaving aside any issues to do with the file-system on which the files reside, are there any inherent gotchas with the export mechanism or the file format that would mean it's not a good idea to rely on this for exporting large VMs...?

Thanks!