Integrate them within a single product and you have a compelling combination. TeamCoherence integrates both tools in one easy to use product, allowing issues to be associated with source files, and source changes to be associated with issues. Why spend large amounts of time reconciling different, and possibly incompatible, systems when TeamCoherence does it out of the box.
The single-user license for Version Manager and Tracker is FREE, and has the same easy to use functionality as the team licenses. As and when your projects expand, you can add additional licenses in an ad-hoc manner as required.