I have a good thing to say about vPOST. Problem: when buying something from VS, I put in my address correctly, including the code that lets vPOST know who it belongs to. This was on the second line of the address. But when I went to pay via PayPal, the address didn't transfer correctly and the second line got left out. So my first response was to email VS, asking if I could change the address. Nope, too late, they said, even though it hadn't been sent out yet. Note: call them in cases like this in the future. Plan B was to monitor the shipment (fortunately there was tracking) and contact vPOST ASAP once it had been delivered.
I'm glad to say, vPOST's system was very good. Once I saw it had been delivered, I went to vPOST's website, to find my package, and entered my tracking number. It automatically assigned my package to me, and I was immediately able to put it on its way to Singapore! Without having to talk to anyone!
I should note, a similar thing happened with HSG, and they were also able to resolve it, although I had to chat with someone. I've heard bad things about vPOST, but this increased my faith in them.