Almost but not there; too many port map issues
I have a client looking for ways to control multiple Macs and iPads scattered around the country, and I thought Screens would be perfect. The software however, hiccups at every UPnP and port map roadblock. There are now a slew of apps able to circumvent these issues- Dropbox and Skype for example - that they use with impunity so having them reset their digital life just for Screens is a nonstarter. I will update this missive should the situation change.
Chasmac55 about
Screens: VNC Remote Desktop, v4.3.1