The two major factors when choosing an international SIM Card are quality and price.  And as you can guess, the higher the quality generally the higher the price.  There is no free lunch with International SIM Cards as with just about everything else in this world, however compared to your domestic carrier roaming rates you can generally save 30-80% on roaming, so for most of us it is worth it.

Service Quality

Quality of service varies greatly when purchasing international SIM Cards and can make all the difference when abroad.  This is the “rub” when looking at all the rates; you need to make sure you are comparing apples to apples in quality of service.  SIM Card quality can be segmented into two parts.

1) Carrier International SIM Cards.

The Carrier International SIM Cards are purchased by wholesalers from carriers at discounts based on the ability to drive significant traffic on the network.  The quality of these SIM Cards are excellent and vary little from carrier to carrier as they are well capitalized and have invested the required upfront capital to have the right equipment in place to complete calls.  Carriers compete heavily in domestic markets and quality of service is a top 3 attribute when customers choose their provider and hence they are forced to focus on quality.

2) 3^rd Party SIM Cards (Non Carrier).

3^rd Party SIM Cards are companies that purchase and maintain a switch and have roaming agreements with the carriers to provide access and service on carrier networks.  In the case of an outgoing call, the traffic goes through the 3^rd party’s switch and is then passed to the carrier to be terminated.  The issue here is that often the switches and the connections to the carriers are not robust enough to handle all the traffic volume; they don’t have the required speeds, and / or don’t have redundancy to ensure traffic flow when servers go down.  All of this requires immense amounts of capital which these smaller companies don’t have access to or are not willing to spend. The quality of these providers does not meet that of carrier SIM Cards in my opinion.  At least I have not found one yet that does.  If you do, please let me know as we are always looking to provide the best value products to our customers.

Costs

As Carrier SIM Cards are better quality there is a slightly higher usage cost generally associated with them. Savings of up to 90% can still be realized depending on where you are traveling to.  3^rd Party SIM Cards can provide even more savings if you are willing to put up with less than perfect quality. Often these better rates are seen in the form of free incoming minutes for specific countries.

Risks

There are risks as well to consider with 3^rd party providers; an additional issue with 3^rd party solutions is bankruptcy and major outages. Over the last year 2 of the 6 major suppliers, United Mobile and 09 Mobile have suspended service for months at a time and left hundreds of thousands of roamers without service.  Neither at the time of writing this are providing service.

In the end it really depends on what you are looking for.  Is quality or price more important to you?  My experience when speaking with customers is that they generally buy the cheaper product hoping there is a free lunch. After using it they come to their senses and buy the product that is a little more expensive but something they can rely on when traveling.