It's way more than a simple dropbox client, it's a integrator of those all cloud storages out there. Pretty useful, have been looking for something like that.

One downside is that there is no Linux version planned (right?).

One thing: "Your first 2 accounts are absolutely free!". What 2 accounts exactly means? Is it linking 2 accounts of those services (like Google Drive and Dropbox)?

Another: on the pricing page, "Perpetual updates" is a pro of getting a paid subscription. How limited is the free version in terms of upgrades?