It's really not the server it's the way your ISP routes to the server. Other streams that your playing have absolutely nothing to do with it as they aren't hosted in the same country so you can't compare the two of them. If it was a server overload as you say don't you think that the forums would be flooded with complaints? It's not so you have something else going on and it could be totally out of your control unfortunately. When people get buffering it's when there part of the country everyone is using the Internet and that bogs it down."x" on the keyboard or "Stop" on the remote will end the spinning wheel of death.
I have unwatchable buffering too, on most, if not all, channels, but only during Pacific time zone prime time. The ISP is not the problem here, it tests fine. VPN or not. And non-Stalker streams play with no buffering in prime time. I believe it's a problem with the Stalker server being overloaded at those times of day.
It hard to watch anything on live tv with all the buffing. Is this ever going too be fixed?
Dot