优点：巨便宜，多选择
缺点：客服几乎等于没有，资费不够透明（有个所谓Fair Use Policy:一周只能免费打300分钟，不可以短时间连续不断拨打电话；如果违反则按照正常标准收费），而且会随时改变收费标准，另一个就是网络电话通病了，通话状况随网络而变不够稳定
综合：追求质量优先商业使用肯定是不行的；个人用户我觉得还可以，毕竟便宜，10USD能用大半年【即使在你时不时违反FUP的情况下】
选择澳洲和中国的话，我觉得2个品牌性价比较高：
voipbusterpro.com，充值15USD，有10USDcredit，指定国家一年免费使用（subject to Fair Use Policy），打澳洲手机不合算0.15/min，其他澳洲固话0.01/min，中国手机0.01/min，中国固话0
In order to offer you the best and cheapest service, we have to use a Fair Use Policy.
We try to prevent that customers with normal calling/texting behavior are bothered by the FUP restrictions.
However when you make a long phone call or many calls in a short period you could get a normal charge afterwards because of these FUP restrictions (the average threshold lies between a maximum of 100 to 330 minutes per week depending on the destination).
Here are a couple of tips to avoid being restricted by our Fair Use Policy;
- Using the call option called "Phone to Phone" via the website and client (pc app) can cause a double call (because this feature calls your phone and the destination number and then connects both lines), this way you can be restricted sooner than you think.
- Call attempts (to the same number) are also registered as calls. If you cannot reach the destination number, wait a while before trying again.
- Do not make simultaneous calls. When two calls are started at the same time, one is always charged !
Remember, the FUP restriction is temporarily and looks at the last 7 days. So just wait a few days and you can benefit from free calls again.