I was asked the other day about using Skype over 3G wireless in Australia. Here's what I said...
I have done some research on how well Skype works over a 3G modem. The result is that it can work satisfactorily in many cases, but may not work in others. It all depends on the 3G reception at your location.
You should seek a plan where there is a trial period so that you can return the modem and cancel the plan if it doesn?t work out for you at your desired location.
You will likely need a 1 to 5 GB plan if you make more than a few calls per week, as it uses 0.5 MB of data per minute. If you find you don?t go near your monthly limit you might be able to downgrade to a cheaper plan.
You will also want to make sure that you get a plan that doesn?t charge exorbitant fees if you should go over your monthly limit.
Telstra, Optus, 3 and others all offer post-paid plans, and Optus at least offers pre-paid so you aren?t locked into a plan. However, you usually have to buy the modem (around $100). 3 also offers a mobile phone that includes Skype usage ? that might work out for you once you take into account the other issues I?ve raised here.
There are other providers who may be significantly cheaper but use the Telstra or Optus infrastructure. Examples are Exetel and Virgin. However, you will will still need to test the coverage issue.