Is Apple Remote Desktop safe / secure?
In general, for remote connections, I would recommend setting up a VPN server on your office network, which would allow access to insecure services (such as VNC, known by Apple as Remote Desktop), without fear of those services getting hacked remotely. Regardless of how secure VNC is (which it isn't), in general it's a good idea to have as few points of entry as possible. A VPN provides this.