Downloads are fine, steaming is also fine. It seems to be just at first connecting to the page. For instance when I link to youtube the page usually loads fine, but the video takes forever to start, but as soon as it starts it buffers just like it normally would by buffering faster than the playback. It's not rubberbanding or anything like it buffered the whole thing before it started.
I don't know much about checking packet loss, or what is acceptable values. Just pinging different ips I get occasional packet loss, 1-14%.