Thanks for reaching out to us. We do appreciate it and are happy to help. In regard to the speed that is needed, really depends on the type of Internet connection that local businesses use, as well as the amount of people that are using the open data at any given time. Remember that if you are at a coffee house and you see 20 people sharing the same network, that could possibly bog down the WiFi. We have a great article that will give you the Network speed requirements for SlingPlayer.
Hope this helps!
The Slingbox Moderation Team