The annual subscription is a one-year plan for using Typemock products. It includes all upgrades and updates, as well as full support provided by our team of product specialists. 
The perpetual license is an ever-lasting license for using Typemock products with no time limit. For this license, the maintenance (which includes updates and support) is purchased separately and must be renewed annually.

We highly recommend staying up to date with the maintenance, as it will assure you are using the newest version and enjoying the product to its fullest extent. When the maintenance is not renewed, the product will “freeze” on its current version and will not support new features and updates (such as integrations with newer versions of Visual Studio and other developer tools).

Isolator Essential is the most powerful mocking framework which includes a Smart Runner for running your tests and Code Coverage which presents your coverage % while you are coding. 
Isolator Complete is for when quality is mission critical. This product includes all capabilities available with Isolator Essential, as well as: Suggest – This first-of-its-kind tool uses Machine Learning and Fuzzy Logic to scan your code and generate the best-fitting tests for you to choose from. The technology behind Suggest opens new doors when it comes to working with previously untestable legacy code. 
Solution Wide Code Coverage – This coverage tool will help you ‘deep dive’ into you coverage and see the % of covered code down to the method level and also allows you to export statistics in different formats.