What happens if the company loses your data? It's a valid concern: Not too long ago, Google temporarily deleted hundreds of thousands of Gmail accounts, and it was days before it restored all of them. Some services, including Syncplicity and Dropbox, provide more detail about the care they take of your files than others.
All of these services offer personal plans, which may be good enough for business use. All except Live Mesh also provide extra features that are especially useful for groups. Business accounts typically offer tools for managing multiple users, meaning you can create accounts and assign permissions, assign new users to multiple files at once, revoke access, allow users to invite people outside the account, and more. Business plans may also provide a pool of storage that's available to all members of the plan, instead of allotting separate quotas for each user. (Google, for one, does not.)
If you work with many different clients, customers, or vendors, an individual account will probably make more sense, partly because you retain control of it independent of which projects are using the shared storage. Fortunately, most services let you put your toes in the water by offering free personal accounts with limited storage, and 14-day or 30-day trials of business offerings.
Box.net is the clear winner among business offerings: It provides IT-style control and administration for groups of accounts. For most other services, business accounts are stapled on.
For four of the services we looked at--Box.net, Dropbox, SugarSync, and Syncplicity--per-user costs are remarkably close. SugarSync is the cheapest at $10 per month per user; Dropbox in the middle at $13.25 for the first five users, and about $10 for additional users; and Box.net and Syncplicity at the top of this short range at $15. Dropbox only allows yearly subscriptions, which dramatically reduces flexibility; SugarSync kicks in a 16 percent discount for yearly payments.
The services vary more in the amount of storage they provide. Box.net's three-user starter plan includes 500GB of pooled storage (167GB each), but it doesn't allow you to buy more. Syncplicity offers the least amount of storage and the highest prices for additional storage: 50GB shared among the first three users, and $10 per month for each additional 10GB--way out of scale with Box.net and Dropbox.
SugarSync is also expensive compared to Box.net and Dropbox, offering just 100GB (33GB per user) for its three-user starter plan, and charging $30 per month for each additional 100GB unit--nearly twice that of Dropbox.
Dropbox includes just 70GB for the starter five-user plan, and charges $17 per month (payable as $200 per year) per additional 100GB units. However, Dropbox doesn't count deleted files or old versions of files against these storage quantities. Depending on how much you revise, this could mean a huge difference in required storage for Dropbox versus other services, which mostly include versions and removed files in the quota.
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