Well they have 2 servers one at each site, so it seems silly to then pay another company to host the data, so i would go with the share based utils.
Fair enough.
I think having a better insight into what they do with these files and how they get updated and by whom would really help to get the best solution here.
So....
Things id be asking...
* What kind of files are we talking about? Documents? Video? Databases?
* Who creates/edits the file/folders at Site A?
* Who creates/edits the file/folders at Site B?
* When user A at Site A edits file XYZ and user B at Site B does the same, what do they want to happen?
* Are the workers who go from A to B also the people that create/edit these files or are they read only?
* Do they want these two sites shares to be merged? is any benefit to this?
* How much data is in these folders at Site A/B?
* How much does this data change over time at both Sites?
* What servers are their currently and what OS do they have?
* What size pipe connects these sites? and what technology? vpn?
* Are both sites within the same AD infrastructure or just seperate?
Things id be asking to validate they dont have any stretch goals on the back on this first job of connecting these shares?
* Do they want to be able to access this data on their laptops when off-site?
* Do they want to be able to access these files over the internet?
* Do they want any control over the files? like version control? audit of who changed which file etc?
* Do they want to be able to access these files on a mobile device?