Best online service for sending an international fax?

I want to send some international faxes to the following countries:

Japan
Australia
New Zealand

Has anyone used an online fax service to send a fax to any of the following countries? Which is the best service to use to send these international faxes?

 

I suppose Popfax.com is the best one, it's 0.06 $/page for any of your destinations. Regards!