I would honestly just use bter.
At the moment I think the Gateways are still bleeding edge tech. People are experimenting with them now, but probably not transferring large sums yet.
bter is quite good and there is much volume. You can really get through the whole process done in under 15 minutes.
Make sure you have an account registered on the blockchain first.
When exporting bts from bter you need to use your bitshares account NAME and not the public key.
Cheers