There is some lag and rubberbanding now and then, it has to be said. It's kind of odd, on official servers it's usually 32/32 and it plays smooth as silk - but then out of the blue it'll start being choppy for a little bit (say few minutes) and then be silky smooth again. It doesn't happen all that much though.
As far as SAS server goes that's another story. When it was early access and we usually had up to 30-ish players it was perfectly fine, but now that it's 40-50-60 most of the time its barely playable. Above 40 its starts to be annoying and above 50 it starts to be unplayably laggy.
US servers are pretty much fine for me, some delay, which is to be expected at ping 160-170, but other than that there is no rubberbanding or any other issues that ive had.
Didn't try the SG server, so can't say.
edit : btw, this is what i get for my internets :
http://www.speedtest.net/my-result/4270802456