What I'm getting from your post, is that you're having problems with the connection speed from a remote location.
In this case, you can discard any streaming restriction as a first step, you can also, try a different port on the router Setup, make sure about hardwired connections and even update the router's software.
Besides that, I would recommend to check the following links.
I'm having exactly the same problem. My box is in Bulgaria and I was connecting with 1300-1500kbps , and i was so happy, i was planning to get the hd box and send it over. From few days it is very, very slow -150-200kb. I am wondering if there is any problem with the sling's servers or the internet connection b/n Europe and US?!