USB versus Pro

Hi. I have Vueminder Pro and USB and have been using the USB version for a while so I can sync between PCs. I've been using it on Onedrive which has it's own problems with sync speed and I was thinking of putting it all on Dropbox instead.
However, having looked at a number of posts online, I've been wondering whether I'd be better reverting to Pro installed on all PCs and using calendar sharing using Dropbox.
Slightly confused so some pointers would be appreciated.
Cheers
Mo
However, having looked at a number of posts online, I've been wondering whether I'd be better reverting to Pro installed on all PCs and using calendar sharing using Dropbox.
Slightly confused so some pointers would be appreciated.
Cheers
Mo